Steal away, I do it all the time. I'm using a Flaming River reversed Corvair box. It is one they are producing that is dimensionally the same as the old Corvair boxes. I am using a stock Corvair arm that you have to modify by cutting four teeth into what were originally flat spots in the splined section. They used those flat sections to locate the arm in a certain position, but it ends up in the wrong spot for most hot rod applications. A half hour workd with a hacksaw and three cornered file take care of it.