From your description, the mounts sounds similar to those found on WW2 military. Do they look like these?

http://www.ebay.co.uk/itm/CCKW-GMC-Engine-Mounts-SET-G508-G506-Chevy-G749-M211-M135-GM-2074268-AFKWX-DUKW-/282018066722?hash=item41a9963122:g:9PAAAOSwubRXH6HO


1941 Chevy 1 1/2-ton WW2 4x4 dump truck
In the Stovebolt Gallery
Lots more pictures