It seems that the taillights (holes), the cluster/dash, and the grille (possibly?) that's in the car are significant clues.
That's not the grille that is in the car, it's the silver streak that goes on the center of the hood or trunk. Defiantly and early 50's Pontiac.
Olds 88 should be 1 piece , it was a pretty common custom modification back in the day to run an olds one pc windsheild in a chevy
If anyone wants to try to get it ... I contacted them and it hasn't worked out yet and I'm wanting it less. It looks like it has a straight-8.