My 69 Dart "AKA" The Blue Mutt
Just finished going through your thread. Nice build - especially your tenacity in the face of constant obstructions.
Regarding the motor mounts, back in the 70s, I had a 340 in my 'Cuda that kept breaking motor mounts. I tried all kinds of things, even solid mounts (I felt like I was getting a massage every time I drove the car). Then a friend suggested leaving the solid mount on the driver's side (that was the one that was breaking as a result of the excessive torque) and leave the rubber mount on the passenger side. This helped take a lot of the vibration out of the car. Might be worth a try.