Vin issues please help

So I picked up a 96 trailblazer for cheap. Needed some work and parts so I got that done. So I got it all ready to ride and can’t find a vin on it anywhere to get it registered. The tag under the seat is missing and the tag that’s supposed to be welded to the frame on the right by the shifter. I know it’s looking like it is stolen and if it is then I would understandably give it back to its rightful owner but I want to know if there is any other way to find out the vin so I can be sure that’s what it is. The only serial number I can find anywhere is on the shifter