[aggie91]

Thanks for all the replys. To jocko's point, unfortunately the OE seat is long gone as are the front fender wells. No SPID anywhere...

What I do know from the VIN is this:
GMC, 2 wheel drive, 250 6 cyl, 15 series, 1973 model assembled in Flint, MI and was the 627,584th on made for that year model.

I know of several sources for a reproduction SPID, depending on what I decide to actually do with the truck, I just might have a custom one made to reflect the custom features that I put into it.

Thanks again for all the feedback!