Sorry I missed this thread.
Most MDT frame rails are 34 inches outside to outside.
Frame rail height ranges a bit. Ford B700's use 10 inch tall frame.
My mid 90's TC2000's (freightliner) chassis are 9 3/4 inches tall
"Don't argue with stupid people. They will just drag you down to their level, and beat you up with experience."
Patently waiting for the apocalypses to level the playing field in this physiological game of life commonly known as Civilization