I was walking through a junk yard a few months ago and came across an old cougar with an empty engine bay ... I noticed that the frame mounts were very similar to the mavs ... I was wondering if a poly mount from an old cougar would work ... But ill bet if you went to napa or autozone and asked them to pull out a mav mount and an older stang mount you could compare and you would save yourself the trouble of finding out the hard way ....
I know for a fact that the Maverick tranmission mounts are the same as those for a 1970 Mustang ,because I`ve installed The used but still good mount that I took off my `72 Mav on a buddys 1970 Mustang to help him out during "hard times"....direct bolt in!
If you get really desperate or can't find frame mounts, I've been running mine for the last 30 years with '66 mustang engine mounts and no frame mounts. They just straddle the horns in the engine bay and have a long bolt going through them, and no one's ever noticed.