1971 Swinger 318, conversion to a 6cyl/special motor mounts needed

I pulled the 318 out and am installing a 6cyl but being I am leaving the V8 K member intact, I need the special motor mounts which allow me to do this conversion. Any help locating them would be appreciated!
OK, I just gotta know why?

In 54 years of hotrodding, never once did I swap to a slanty, lol.
Altho, I did rebuild a few.

If it's for fuel economy, that's almost a myth.
I'm pretty sure that I can get better fuel economy out of a hi-compression, modest cam, overdriven M/T 360, than any factory non-overdrive 225slanty ever made; and I'll give you the benefit of choosing any Mopar trans and any Mopar rear gear.
Your 318, properly rebuilt, can do even better.

If it's cause the 318 is wore out, and you just happen to have a slanty with a transmission, well that's another matter.