I say go for it. It’s only mounts, a trans crossmember, and a torsion bar crossmember. Same amount of work to do almost any overdrive trans and a gen 3 hemi. Do it, put turbos on it, make 1200 hp and drive the **** out of it. Who cares what a bunch of purists think that never drive their restored junk.
The problem isn’t the mounts, it’s the headers/exhaust that become the issue. When Jared put the coyote in his Duster (with coilovers) he had to make extremely restrictive headers just to get them to fit.