O500 swap
Unaware of any ready made mounts. The torsion bar crossmember of the unibody needs to be modified to allow for the OD section of the transmission, and the rear mount needs to be modified. In all, not too bad if you have a sawzall and a mig welder. You can't just cut the crossmember away, it supports the weight of the front end.
I plan to use a 42RH in my 65. I'll post pics eventually, but the project is on hold due to lack of cash.