I am normally pretty good at these but I'm stumped. I found a huge GMC in a junkyard I can buy. It's not really what I'd call your typical cab over and it not a small truck. I'm guessing 54 55 due to the windshield. I can get titles through my state on stuff like this using the VIN/serial number on said vehicle but I can't decode this VIN to figure out the year. Everything I find is for a smaller truck. The VIN has been checked and cleaned off and this is for sure the #. W624 42 Z11xx Can anyone decode this one.