[M5-]

Well I haven't had time to do the pencil test but I did pull the seat out of the truck and got a better look at the build sheet. If I'm reading it right the seat must be from a different truck as it states the color of the truck as turquoise where it's obviously yellow. That explains quite a bit. Unfortunately the serial number on the build sheet is ruined so I can't read it all but what I can see doesn't really match any of the numbers in my vin.

All this is leading me to think that the engine in there is in fact the original motor and is a 250 even though the truck is titled as a 65. The engine was cast in either mid April 65 or 75 and the head is a 230 65 version. I have 04 Duramax that is an LLY but they also made an LBZ in 04. Because my LLY is early production it still has the LBZ tranny. GM has been mixing and matching for years and they still do it.

Being that the truck probably wasn't assembled till May of 65 I'm leaning towards it being one of the first 250 trucks ever produced. My vin shows it as the 43000 and something off the line in Janesville in 65. It'd be really nice to find some early production numbers someplace.

M5