Yes, Reid SFI rated bellhousing and Lonnie of Extreme Automatic's CNC'd adapter. It isn't the cheapest way to go, but they have top-shelf customer service and put out a great product. The transmission's gearing with 3.91's or 4.10's is perfect for launching and high speed freeway cruising. It feels like a 5 speed. Not sure why someone like Art Carr cant figure out how to do this, but the lock-up converter is something I would never want to be without. Even with a modern high-efficiency, high stall torque converter, mine drops at least 300 rpm on the highway when it locks-up.
I did use a high quality torque converter with 3000 stall and 3 carbon fiber lock-up clutches from Precision of New Hampton, ask for Milt. The overall length of the converter is critical get right. This allows a certain amount of freeplay for the converter once the bellhousing/trans and block are all bolted up. Too tight and the converter is pushed into the transmission causing damage and too loose and the converter can come out of the transmission disengaging the pump tabs etc. Its not hard to figure out, but it must be within spec. Milt has those measurements for my small block. They should be the same on your big block, but he can guide you on that.
Here's a few pictures to give you an idea of why someone might want to spend the money on this combo. I drove the car nearly 400 miles each way to pull off a win against a Hellcat, several other modern Hemi powered cars and a bunch of other vehicles, and I got over 18 mpg on the freeway at 80 mph. This was with only 410 hp. I'm upping that to just over 510 in the next few weeks.
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