Big block / small block

Well the truck had a 318 poly in it..... and it is broken beyond repair.... I wanted to adapt a 360, but they're tooooo pricey around here (western NY) though I don't see why..... There is a 413 near me, that needs some work, but I think it would be cool to make it fit! I have access to milling machines and a lathe, and know how to use them (well most of the time anyway) and wanted to make a bell housing adapter to make either the SB or BB mopar fit my poly bell housing. Doable ?