1Bad67 - the tempest four is unusual engine, most have not seen one, so I understand why no responses to your question. I like Pontiacs, put together exactly what you are asking about back in 2008. It’s stock rebuilt engine, pg out of 1966 chevy II, mopar 8-3/4, mine is in a red. Modified the stock pg output shaft to shorty, I bought the aftermarket rear cover to replace the stock pg tail housing. For dimensions, if you make your own rear cover, that will provide the dimension you need to cut the pg output shaft to make it a shorty trans. I removed oil filter housing (conflicted with chassis) and made a aluminum plate to cover it and also used that plate to mount new mini-starter. Due to the thickness of the crank flange, you will have to use a thicker than 1/4 inch mid-motor plate. Or have a special torque convertor made….
The red chassis I bought from 2nd owner in 2003. The original owner, his friend was there when I picked it up in LA, met and talked to him too. He said he had Don Long make this chassis for him (no way for me to prove it). It had a blown sbc in it when I got it, blown as in window in #5 cylinder. The front end is more like a early fed, everything on chassis nicely done. The bottom rail front to back has a slight upward arch in it, the wb is 198 and 200 side to side. Last time I ran it at Speedworld in 2010, it went 14s at just over100 mph. It’s been sitting for 3 years now….. don’t have any plans for it, but was fun project to build. Any questions, please ask. DF