I just got told that only another slimjim could be swapped did not want to touch putting in the TH400. I know there is some modifications to be made, but the TH has a fresh professional rebuild and not many want to tackle the Slimjim. Anybody know of a brand of adaptor plate combo that would be needed.and anything else that I would need.

 

Contact Tony at Ross Racing. He sells conversion kits for turbo 350 and turbo 400 but I think they include the transmission. Here is the link

http://rossracingengines.com/c/5/old...early-catalog/

 

Here's another option:

http://www.transmissionadapters.com/early_olds.htm

 

Connecting the TH-400 to the engine will prove less a issue then the floor pan mods needed for case clearance with the new transmission. Not ball peen hammer mods by any means. Good luck

 

The Tony Ross conversion requires little to no floorpan modification.
The Bendtsen's kit would require major floorpan surgery.

https://classicoldsmobile.com/forums...-slim-jim.html