You're talking about doing a backhalf, cage, (frameties?), narrow the rear (doesn't matter if it's an inch or a foot, takes the same amount of time), tubs?, sheetmetal? 100 hours, or even a little longer, is about right unless the guy's a hack. Plus material.
Again, is he full time in a well equipped shop or in a shed behind his house with a floorjack and a Home Depot welder?
If the results don't match the theory, change the theory.
