I have been running FR4 plugs with the Edelbrocks heads. The Edelbrock recommended plug is a Champion RC12YC.  I have never had a Champion plug I liked and I saw many of them being returned due to failure in vehicles.  Two plugs were recommended here. One is the NGK FR4, the other BKR6E.  Remember, this is a factory dual quad car that is street driven with the occasional "blast".  There is some soot on the body, which I am a bit rich but much I see a lot of gray on the electrode and ground. I had a set of BKR6E in my cabinet. Any reason not to run them?
Is there another recommendation?  I might add that I am also running the Pertronix II and matching coil. Direct 12V power source to the module as instructed. The compression ratio is about 9.8:1.
Any suggestions would be welcome.

I maintain about 18-20 PSI at Idle ( 900 RPM) and about 55-65 at 3500 RPM hot.  I changed to Valvoline VR10-30. Does that sound about right?

I have been doing primarily street driving. I have started doing short freeway runs. Being it turns 3500 at 70, I haven't taken it on a long trip. 
I have been noting that when I come off the freeway and hit a few lights that the temperature starts running about 20% higher on the gauge for about 20 minutes post exiting. Is there a reason for this?
                                                                      -Keith

I have been having an issue with the dipstick being pushed up about an inch. There isn't a blow-by issue.  Sometimes I have to rotate the dipstick to get it all the way down.  I thought perhaps it's getting hung up on the windage tray? 
I have a PCV valve that is vented from the right rear intake boss ( C7ZX 427 MR intake)
I thought perhaps others may have encountered this in their travels.
                                                                                                              -Keith

I rebuilt my Toploader. The kit came with a new shaft and of course I used it. However, I noted some gear oil on the inspection cover and along the bottom side of the case. It's also getting on my coated headers.
Is there a way to seal the front side without removing the trans or pulling it completely out of the vehicle that anyone could recommend?

                                                                       Keith

After a few bugs I think much has been worked out.  I had a new Mr. Gasket 180 degree thermostat stick in the open position. I replaced it with a Robert Shaw 180. Immediate change in temperatures, but still running warmer than it was previously.
The alternator is a dual belt unit. When I put the new Marti belts on they have the Ford white ink printed numbers on them. I lined up the printed information on both belts when they were installed. When I checked the under the hood post my drive with the new thermostat I noted the belts were no longer lined up. That was proof that the belts were slipping.  The NOS ford temperature sending unit had arrived as well.
I loosened the alternator back up, lined up the belts and made sure to use a pry bar to apply more tension on the belts.

I removed the distributor cap, sat it on top of the front carburetor  and pushed a rag in around the distributor to retain any coolant that may come out of the intake when I removed the temperature sender to replace with the NOS Ford. I noted a huge amount of air was vented and very little coolant. Of course I was quick trying to keep down the mess.
I didn't loose enough to justify adding coolant. I went for a 15 mile drive. The vehicle ran at about 1/4-3/8 of the gauge the entire time.

My presumption would be that there was air in the cross over in the intake to the heads and that the belts were slipping under load which would have impaired water pump and alternator function.

Hopefully this will address the hot running engine.
                                                                                      -Keith

I put 20 miles on the Shelby's new engine last night. The other engine had C6AE-R with about 11:1 compression.The Edelbrock  heads and JE inverted dome pistons have me at about 9.9:1 compression.  I have the Edelbrock water pump as I did before and a ford factory radiator with a heavy duty three core. I am running the factory fan, shroud and and clutch.
I have changed to Edelbrocks, but everything else pretty much remains the same.  The other engine seemed to be a constant at about 1/2 gauge or just below.  It seems to come up to temperature much faster as well  I have the high flow Mr. Gasket Thermostat that looks like the Robert Shaw. 
It is also supposed to be a high flow. I did accidently drop it during assembly. It didn't appear to have damage. Are is the Mr. Gasket a decent unit, or are they Chinesium garbage that tends to fail?