In between shortening the stock steering shaft and the Nova sub frame installation I ran a Vega box but after a while it proved too light weight for the car. Remember a Vega was light and had a four cylinder. To mount it I made a plate out of 1/4" plate to mount it to the frame. I used the three stock mounting holes to mount the plate and at least one of the Vega box mounting ears and drilled other holes in the plate as required. I ran a gusset to the outside lip of the frame and drilled two holes in the lip to bolt the gusset to. As far as the pitman arm, the splines are different so I took the Vega pitman arm and cut off the end that the tie rod would attach to. I disassembled the '46 pitman arm, removed the two mounting studs and stacked the Vega/'46 arm to resemble the stock '46 arm. I then had an extremely competent welder weld the two together. Never had a problem with the arm. You could probably do the same using a manual box from a larger car such as a Nova/Camaro/Chevelle full size Chevy.
