'65 Cuda - 273 rebuild or swap?

I have practically the same scenario as the Yellow Signet that I purchased in Colorado last week took a dump in Susanville California driving back... Luckily I have my 87 Mazda p/u with it's 318 injected Magnum and 46re trans complete with harness and computer, jet chip and running excellent to swap out. I figured I've got maybe 1500 in the Mazda and that should be equivalent to what it would cost me anyway.. I think it's a good choice and the transmission mount could work as well..

I'd say, forget the rebuilt and find a good running Dodge truck on Craigslist needing much body work and discard the body unless you can find some hot rodded thingie like I did... :)