Regarding what the original 13-digit VIN is, there are only two possibilities:
JH23G4B338627
JH23L4B338627
They were all
JH23s, they were all
4Bs. You have the sequence number, so the only digit open to queston is the engine code. A 318 car has a
G in position 5, while the high-perf 360 would have an
L.
I'm assuming that mis-stamped digit in the sequence number is a
6, based on what that numeral looks like in my own cowl. You could do a title search in your state, or some other state in which you think the car may have spent some time. If you come up with hits on one of those VINs--
both can't exist--you've found your car. Depending on your location, a title could be nearly impossible... or it could be fairly painless. My car came from a "no title" state (Alabama). Getting a title in my name was a freakin' cake walk, since the car was not stolen. They never even wanted to look at it.
My 1967 GTX was a different story. Even though the VIN and fender tag showed the car's real identity, the title the guy had gotten with it was for a 318 Satellite. He never bothered to look closely at it. A quick search through records in the car's original state (Indiana) indicated the car had been stolen in the early '70s. A
lot of effort was made to hide the car's identity, including an extremely-thorough repaint--yet all the GTX-specific stuff was still on the car (flip-top fuel cap, emblems, hood). It was Turbine Bronze when I got it, but left the factory as a Light Turquoise car.
The statute of limitations had long-ago expired but to avoid raising red flags, I parted rather than restoring it. So many original parts were gone like the engine, trans, and OE axle anyhow. A friend still has the bare shell in his yard, but he's never going to do anything with it. I still have the VIN and fender tag... right next to the 318 Satellite title.
