No one has mention alloys to strengthen block castings. Does CGI ring any bells? What about the other alloying elements like nickle, manganese, tin, copper, etc? Alloying iron/aluminum will allow material to be removed from low stress areas [think "thin wall casting"]  without affecting the overall strength of the casting itself.

anybody ever heard of a vent blocked causes it to leak out a seal

A possibility and easy to check. One bolt at the servo and it is loose. Let us know what you find. To add: After 35 years of hard use that C6 doesn't owe you a thing.  With that said perhaps its time to just do a "freshen up" on that trans and go for another 35 years.

Front main seal most likely.

Not to open up a can of worms, but indexing on old vintage engines where the sparkplug is not ideally placed, poor combustion chamber design will make a difference.  On the newer combustion chambers with the plug placed near center, or aimed toward the exhaust valve, no difference.  I did several tests on my EMC engines, and did not find any help with power due to good chamber design.  Joe-JDC

To expand a bit on plug indexing, in the early/mid 60s it was done only for the ground electrode to clear large dome high compression pistons such as on SBCs. It was one of those "magic speed tricks" where racers saw it done on good running race cars and thought it was new found horsepower because the winners were doing it so they need to as well. Joe, I never heard it even helped lousy combustion chambers. How much hp did you see by indexing plugs with poor combustion chambers?

Quote from: RJP on October 28, 2020, 02:22:32 PM

I had a front wheel bearing go bad on my 66 Galaxie as we were coming thru Grant Pass, Oregon on our way home from Canada. Got off the freeway and as luck would have it there was a auto parts house about 1/4 mile away. Pulled into the parking lot, pulled the wheel and found the outer w/b and race wiped out. Parts house had the wheel seal but didn't have the bearing, out of stock. The parts man suggested I call the wrecking yard that was about a 1/2 mile down the road. The yard had a complete wheel hub, bearings and drum and offered to deliver it since he was closing in a few minutes and would be driving by the parts house on his way home. Few minutes later he pulls into the parking lot and hands me the drum, I ask what do I owe you and he says "How 'bout $15 bucks?"

Was the parts house behind a ARCO station?

I got 2 stories:
First, I got back from VN in July of '67 and bought a '64 Fairlane Sports Coupe, with a factory 271 hp 289/4 sp. I was in Orange Co and had to drive to Ft Lewis, WA (Tacoma). I heard a noise in the Rt front, about 100 miles from where I was going. The car was only 3 years old and I couldn't imagine a wheel bearing going out. I pushed it to within 10 miles of Tacoma and the enter race, seized on the spindle. Off ramp was close and went to a phone booth a called a tow truck. He took me to a garage and they let me use a floor jack and their cutting torch and only charged me for the wheel bearing. 

In '78, I had a '67 Cortina (loved that car) and when on I5, in the Sacramento Valley, 40 mi from anything, it rolled to a stop! I always carried a tool box, in those days. I opened the hood and looked around. I couldn't fix it with tools!!! The pressed in inlet to the carb, came out. I knew if I just pushed it back in, it would do the same thing 

I looked around and found a alum beer cans, I then formed it into a shape that would push and hold the line in. I made it another 500 miles, to where I was going.

Its amazing how creative one can get when there is no other alternative. RE: The Grants Pass episode. No, there was no ARCO station, no nothing on that end of town except a few old houses, the parts house and the wrecking yard about a half mile away. I wasn't about to go on a sight seeing tour of G.P. on a bad wheel bearing. Another "Make do with what you have" story... 4th of July weekend at Lake Tulloch towing my boat with my Lincoln MKIV...We were leaving Sunday AM to avoid the 3 day weekend traffic. I get about a mile from the resort and something just doesn't feel right. Pull over and check wheels, Driver side rear is dripping oil, uh oh, not a good sign. Pull the wheel and drum and I can wiggle the axle about 3/4 of an inch up and down.  A friend was with me towing his own boat so we left my wife with the car and went into Oakdale. Called a local guy that was working in his shop...He was listed in the Yellow pages. Called him but he refused to help claiming that his weekend is his and his alone. I then asked him then why did you answer the phone? He snapped back and said "habit" and then hung up...What a guy! The local Napa store had the wheel bearing but no seal...[Hummm..Is there a wheel bearing pattern here?] With new bearing in hand we found a local tool and equipment rental store open, went in and asked if they have a press? The very nice lady at the counter said yes but I don't think it works but you are welcome to try. Press has 2 leaking fluid lines so after repairing their press I got what was left of the old wheel bearing off [Just a bare race] New bearing pressed on but no seal to install. Back to the car, axle installed and didn't give the seal another thought as the brake shoes were already oil soaked so no matter. New bearing got me home with no more drama. Do I feel like I'm a 'Mac Gyver'? Hell no...This is real life, not television.

Beautiful job, Jay. I also love the color.

I think you have found your problem...the converter. It should not sound like a box of rocks rolling down a hill. At this point it would be a waste of time and money to have the converter split and inspected. With what you have described it would not even be worth core charge. Regarding the case p/n of D3TP it sound like it is from a truck but the main thing you should look for is the detent mechanism for the shifter. Early shifters use a ball & spring in the valve body and later, say in the 73-74-75 range [I don't remember the exact year] they switched to a "rooster comb" and a loaded flat spring/roller so be careful about purchase of a rebuilt v/b if you choose to go that route. As for the internals of the v/b there are a couple of differences such as check valves and I believe spring tensions so if you do a shift kit you need to know what vintage v/b you have. If it were mine and the trans is out and on the bench I would do a complete rebuild if for nothing else to clean any debris that seems to migrate thru out the system after a component failure no matter where that failure is. Also it is a good time to inspect for any pending component wear, damage and such and to bring all component clearances back into spec. Don't assume the converter debris is confined to just the converter. You will need to flush out the cooler lines and heat exchanger before putting a rebuilt trans back into service as fluid from the converter goes to the cooler before returning to the output shaft support bushing and sprag clutch. Look for damage to the sprag rollers and races along with junk getting into the main support bushing. There are commercial flushing kits available to do this. 

55 or 56 Ford 2 door sedan...That would be cool.