Big block radiator vs. small block radiator?

I'm building a 512 stroker for my 71 dart.

Right now I'm running the old 318 and my radiator is garbage. I'm wondering if I can buy a new aluminum rad and use it now on the 318 yet still hive it be the right radiator for the big stroker?
I'm not looking at the motor but seem to remember the H2o outlet is on the other side on the BB?