340 swap-small block k frame or motor mounts?

Hey there guys,

Im getting ready to swap a 340 into a 1971 Scamp which currently has a slant six in it. I can either buy a used K frame for 250, or go with schumacher motor mounts for 300. Im debating which route to go. The car will be a street car, if that makes a difference. I was just wondering if one or the other will affect header clearance or will require extra fabrication to work. I just want to go the best route for the money. Considering the mounts are only a little more than a used small block k frame, the mounts seem like a better idea, but im not sure, so please steer me in the right direction.

Thanks