I use an Extreme Automatics Stage 2 2004R with a Reid Bellhousing and a 3800 stall Precision of New Hampton custom 3 carbon fiber disc lock-up clutch. It's the best automatic transmission I've ever used. It's relatively light, compact, stout (when properly built) and the gearing is as close to perfection as I could imagine.
I had to modify the torsion bar crossover frame, but didn't have to cut the floor. I also had to make a rear engine crossover bracket and smash down the pinch weld around the bellhousing.
Lonnie over at Extreme Automatics sells a complete bolt-in package.
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