flathead 6 to a slant 6

I've got a 46 dodge pickup with the 218. It's out of the truck and needs to be rebuilt. Instead of spending 1000's to rebuild I've got a slant 6 with a 904 torque lite from a 64 belvedere all ready to go.. anyone ever tried this? Curious as to how to go about making the engine and transmission mounts.. Any ideas guys? Thanks!