Measure Twice, Cut Once!
These measurements work for bobbing an M35A2 or A3 using either M105 springs or Deuce springs and an M105 bed with the original rear-most cross member (the one with the pintle hook and bumperettes attached) re-installed at the end of the cut frame rails.
I recommend you test fit EVERYTHING before you fire up the cutting torch!
If you will be using the bumperettes, cut at 100 3/4”.
If you are going with a “flat” bumper, cut at 112 1/4”.
Either way, the driveshaft will need to be lengthened 5”.
Once again: Test fit EVERYTHING before you fire up the cutting torch!