Well, that solves that mystery! I even searched "AMT kit 029-5539", but this didn't come up. Didn't think about MPC. Actually got the parts from a modeler in Canada back in 2018, but there was no return address on the box with the White-Wester Star in it. Post mark was Ottawa.
Maybe. I really have no idea. Searching for "Revell kit 029-5539" brings up just about every imaginable type of kit from the USS Constitution, to aircraft, & Star Trek.
Several years ago, I purchased, or traded for, an AMT White-Western Star kit; and this was in the box as a "bonus":
It even says so on the plastic wrap. The tree is labeled 029-5539. Does anyone have any idea what kit this might have come from? Looks like dragster parts to me.
I haven't built a 1957 Chevrolet either, and I have been considering this kit. So there are a couple of us out there.
I did an AMT 1955 Bel Air back in October 2019, though.
Nice job on the Peterbilt, Jason. If I remember correctly, when I built this kit (and the snap W900), I had the same issue. From what I remember, the pins on the grill are too long & hit the radiator. Check into that. It might be your issue, too.