Can you install a 350turbo trans to a 231 6 cyLinder engine?

It should fit. You see, a 231 6 cylinder is a shortened 350 V8. GM engineers simply cut 2 cylinders off the 350's block to make the block for some of their 6 cylinders (the 225, the 231 and the 234). The 231's were used in Buicks, mostly.

no way the Buick 231 has a completely different bell housing bolt pattern, but don't take my Word for it, fust look at the top of the bell housing on the motor and trans, the Buick comes to a point in the middle and the Chevy is flat. although they are both gm products the buicks and chevys are not interchangable, sorry