Welcome in, My3suns
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Roy... they're so close ! ... the bolt pattern on the flex-plate... not interchangeable though. DEFINITELY no big deal. ANY generic 168 tooth ( the big one ) flex-plate or flywheel from a 70's/80's 350 Chevy will work just fine.
I believe that 235 "big block" 6 is coupled to a cast iron "2 speed Power Glide tranny" ( hereinafter referred to as a "glide"
: ). I know that the bell housing is a VERY peculiar thing, and will not bolt up to any Chevrolet V8 engine ( or 62 & newer 6 cyl ).
In this case, I'd have to recommend changing the transmission to a "short tail housing" aluminum 'glide. They were first used in 1962 327 cars ( and Chevy II ). If you can find a 62 version... it's a DIRECT bolt-in. If not, I have found the 64 model to have more compatible linkage than the 63..
.
Changing to the aluminum 'glide will also solve your kick-down linkage pronlem, as these parts are EVERYWHERE ! ( need some ? ... HHMM ?
).
Other little things that I see you'll need:
Frame mount pedestals ( stands ) for a V8... available used from ANY 1959-64 Chevrolet or CDN Pontiac car that had a V8 engine.
A V8 throttle lever for the firewall ( you need the arm only ). Any 59-64 will fit... however, there are a number of different designs. To try and be correct, I would attempt to find a 1962 ( one year only ) part from a 283 car.
Hope this helps
BTW... no matter how much work this conversion is... you WILL KNOW it was worth it
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