Brian, as far as I know you should have the same tranny and rear-end as any other '46 Chev./GMC, but with a short driveshaft extension between the back of the tranny and front of the torque tube to make up for the longer wheelbase. Do you have an extension there, about a foot long? You are sure about being a 1/2-ton (6-lug wheels)? In those years GMC made 1/2-tons with both a short and long wheelbase, Chev. only made short 1/2-tons. I would guess Patrick's 3.55 gears would fit your rear. If you want to be sure, pull the gears out and bring them up here, I've got a set of Patrick's gears on the shelf we can compare them to.
