OK, so I have some industrial universal isolators. Time to find a chunk of 2 x 4 tube to make the mounts. The isolators have a 0.9" height over their support. The 2 x 4 tube with a piece of 1/2" flat stock for the support and the re-bound washers and I have 3.5" above the frame and isolation of a modern truck. Pictures when I get them finished.
I may have also found a surplus rad in our inventory.
Scott