Motor Mount modifications for 340/360 into Early A

That 273 3 holer is bizarre. My 64 273 on a dolly in the garage is a 3 holer too, 2 in the FRONT and one in the back, driver side only, passenger is opposite. What were they thinking putting the mounts all over the place? I remember boltin my 65/340 up but cant remember what side I had to shim with washers. It was only on 1 bolt hole, sort of a spacer. I later made the triangle cut and weld.
I have a 64 Dart GT with a 340 and a stock motor mount on the passenger side but on the DRIVERS SIDE I HAVE JUST THE METAL PART OF THE PICK UP TRUCK MOUNT !!! ONE SOLID MOUNT!!! NO I REPEAT NO RUBBER MOUNT ON THE DRIVER SIDE! BOLTS IN JUST LIKE IT GREW THERE FROM THE FACTORY. It would be very easy to recommend that if you were to put a HI-PO 318 or 273 into one of these cars the solid mount would seem to be very practical just use a 318 drivers side mount.
1 solid plus 2 rubber mounts usually equals a cracked something....but I agree that the 318 truck mount (or even the 360) is a great starting point for a custom mount.