The exhaust manifolds will interchange between Olds and Buick. The only difference is how they mount on the block. You will need a turbo intake to change over from the 4 brl which is stock on all Buick Specials and Skylark’s.
The turbo-engines are worth a LOT if you rebuild it right, keep it original, and do not put it in the wrong car. (Good in: Oldsmobile Jetfire from 61′-63′.. Bad in: MG’s, Rover’s, Buick’s, Pontiac’s, Oldsmobile F 85 and Cutlass Models.)
The turbo in the condition of needing to be rebuil is not worth much more then $750., but if it works and is complete (Bolt in and drive) could range from $1250-$1750. depending on condition of course.
I think it would be best to transfer the turbo onto an Oldsmobile 215 since the heads bolt on differently, same with the valve covers, and sometimes an F 85 will have a 2 brl carb and intake.
I do have a 1962 Oldsmobile F 85 215 in an unknown condition. Of course it will need to be changed over to a turbo intake, turbo exhaust manifolds and all the turbo related parts.
Just my opinion. But it is always your car, unless you wish to sell it. So build it for yourself!