Engine charts with weights are all over the Internet. Consensus is;
SBC 575lbs
BBC 685lbs
Cad 625lbs
Your 472-500 series engine is roughly right in the middle weight wise between a SBC and a BBC.
No BS, no gun smoke, no educated guess.
With an aluminum intake you will be close to SBC weight, pretty cool for a 200 ft. lb. increase in torque!
Other than lengthening your distributor wires the rest of the engine loom should work with your TBI sensors attached to the Caddy engine.
I would consider a BBC radiator and shroud, I think Larry did it in his Polar Bear Suburban build.