1972 OLDS TORONADO FOR PARTS OR WHOLE | eBay
Heres a 72 toronado parts car.
Jerry one thing you haven mentioned is the envelope the Cord gives you to work with...
How wide can you go and not have the wheels stick out the fenders? How wide can the engine be and still give you room to work (plugs, exhaust, steering linkage) Most of these cars are going to have floor mounted shifters, I imagine a company like Shiftworks could help you come up with a dash mounted gear lever (the corvair and some others had a dash mounted automatic lever in a bezel). You may have to get one of those and adapt it to the 3speed of the donor vehicle, or go with an aftermarket column with column shift.
An olds 455 is a fairly large motor, but several can be adapted to the FWD setup, assuming you can stuff the toronado/eldorado front end under the Cord (gosh its still weird typing things like 'stuff it into a CORD')
Several years ago (before digital cameras) I helped stuff a gm iron duke 4cylinder and 5speed into a jeep pickup truck (converted to 2wd). The guy who was doing this, found fabric wire coverings to slip over the modern harness and he had a vinyl graphics company redesign some stickers to make it look more factory. It came off pretty well.
I realize you're a bit older than some here, maybe if you gave us some envelope dimensions, we can paw around in our yards and give you some more accurate ideas