I've built two C6's using the Motorsports wide ratio roller bearing kits, they are pretty straight forward and complete, but I will note one thing - the instructions in mine said to use forward clutch drum E9TZ-7A360-A, which is machined and clearanced for the roller bearing assembly, instead of the forward drum the earlier C6's used with the solid thrust bearings. The problem though is the E9TZ-7A360-A drum had been discontinued by Ford a few years earlier and replaced by a F81Z-7A360-AA forward drum. The F81Z-AA drum will not work with the kit because it does not hold the C6 input shaft in the proper place ( it allows it to slide rearward ). I was able to have my Ford dealer locate a couple obsolete new drums using their locator service, but that was quite a few years ago now, I don't know if there are still any out there, sourcing a good used E9TZ-A drum may be the only option ( which is fine ), or it may be possible to machine the pocket deeper on the earlier C6 forward drum. I don't remember off the top of my head if the instructions had advice on that, it may have. Otherwise the Motorsports kit assembled fine, everything fit fine, and there were no issues. The final geartrain endplay still needs to be checked & set, but that is done as normal with the selective #1 thrust washer, and you may need to obtain the one you need from a transmission parts supply business if you don't have a selection on hand, but they are easily purchased.
As far as any other things to do, do you know how many Reverse-High ( Direct ) clutches your current drum holds? I usually use a 5 clutch drum myself. 5 clutch Reverse-High ( Direct ) drums were used in some high torque C6's stock, and are available from most of the Transmission supply businesses. Ford Motorsports used to have one available too, but it has sadly been discontinued. One was for sale on the forum here recently, but was snapped up quick.
I've used "H" servo's in my C6's, some already had the "H" servo, or I've been able to find some used ones when needed. They have functioned fine, but I'm not pushing an extreme amount of power.
Do you know what year C6 transmission case you have? The '66- to somewhere in '69 C6 case used splash oiling for the one-way clutch at the back of the geartrain and was prone to failure. Starting in '69 Ford switched to a pressure oiled one-way clutch. It's very easy to convert an earlier C6 case to the pressure oiling, and the Motorsports wide ratio roller bearing kit comes with the proper pressured oiled one-way clutch inner race, if you have an earlier case let me know and I can detail what needs to be done, if you have a later case it will be set for the pressure oiled one-way clutch already. Even if someone isn't doing a performance C6 build it's well worth updating to the pressured oiled one-way clutch, almost every old pre-'69 C6 I've worked on had a failed one way clutch, or was on it's way to failing.
I always check the pump gears and replace if needed, they are relatively cheap. I always have a new convertor bushing installed in the pump too. I generally have my mechanic buddy BradFord install the pump bushing because even professional transmission shops don't seem to know the proper direction to install it ( the bushing has an oiling slot ) and if done the wrong direction it can result in seal failure at some point.
Jim I'd be happy to give you some help if needed, but I won't be able to until August, I don't know what your time table is, just let me know.
