We got a winner. The perfect combo would be the LS4 engine with the F40 transmission. If you are willing to cut the frame (close to the tranny) you can use the E153 with the LS4 as well. The LS4 is very compact measuring an outstanding 23.25 inches, if we use it with the F40 which measures 14.30 inches that means both combine would come up to be 37.55”
not sure what the "small GM V6 bellhousing pattern" is, but it sounds like it might be the F40 pattern. http://en.wikipedia.org/wiki/List_of_GM_bellhousing_patternsLS4 is the poor stepchild of the LS series. Used in FWD cars with transmission mounted starter. Small GM V6 bellhousing pattern.