[PGSigns]

I had a 64 with a 402 in it and liked the power but not the nose heavy truck. For me it killed the handling. I had the truck for years with a small block. If the burb has a Vortec head small block in it I would freshen it. I have one in my 66 and like it. My Burb is getting an LS. Just hard to beat the power, fuel milage and the weight off the nose. If you go with the BB you will need set of mounts, a 4 core radiator, trans mount, maybe a high hump to clear the turbo 400, a trans yoke for the 400, a drive shaft to match the length of the 400, a trip to the junk yard to get a cross member from a 73 to 87 with 1 1/4" rotors, the power steering and the power brakes. The list goes on but that will get you started.
Jimmy