The only way you are going to get a T56 behind a pontiac is with the aftermarket version of the T56. It's the same one they sell to mate to the T5 bellhousing. The input shaft is not too hard to do, but requires some special tools. A tranny shop could probably do this for around 500 bucks. The yellow 69 Camaro you are reffering to is the Twister, and Kyle Tucker switched input shafts to use the Viper T56. Mark Steilow has been doing this for over 4 years too. I have yet to convert a LS1 T56 to a first gen, and don't know about the clutch. I think you could use the clutch as long as you used all of it with the hydrualics. You would need a 1pc rear main seal for that. As far as a pontiac, you are very limited to T56's that you can use. The easiest and cheapest is the afterarket one.
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