I myself would keep it all Buick. If you put your '56 on the lift & next to it put a '61-'65 Full size or a '63-'70 Riv. on the lift next to it you will see that everything from the donor car will be there that you need. Do some careful measuring & swap out brackets & other needed parts as nec. The engineering has already been done by Buick & all you will be doing is making a mirror image of what is being removed. The added advantage is you will be maintaining the 12" brakes that the '56 already has. You could try designing your own set-up, upgrading brakes, along with the engineering & learning curve nec. to accomplish the proper engineering nec. for suspension travel, geometry, etc. But IMHO why bother when it's already been done & proven.
Just my thoughts on the subject.
Classic and Muscle Automotive
12 Cook St.
Norwalk, CT 06853-1601
Day Phone 203-324-6045 ET
NailHead Mini-Starters '53-'66
Adjustable Roller Tip Rocker Arms - All NailHeads
Custom forged pistons
Front & rear neoprene seals
Many other "Nail" parts
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