Seeing as you are thinking about a V8, a 190 wouldn't suffice would it Rick?
You would need a rear subframe from the V8 then a lot of work on the boot floor to accommodate the change.
Then the tunnel would need altering to fit the engine and box of your choice, front subframe would remain largely the same just a slight alteration to allow the routing of the steering components.
Anything can be done, its just time & money.
I have always hankered to fit the old Buick engine from the old rovers into a 75 shell, then again, a nice 350 chevy would be good too...