[1968_K20_4x4]

I am assuming that the motor in my truck is not original because of the casting number on the block, which decodes it to a 1969 motor. My truck is a 1968 according to the vin. I unfortunately do not have the spid, build sheet or any other info to indicate what motor the truck came from the factory with, other than according to my vin number it was a v8 truck. I do not know the build date of my truck nor do I know how to check it. If this motor I have found for sale originally came in a truck with the th400 I think I will keep looking until I find a block with a YX stamping to make it correct to my truck. Or a whole 1968 parts truck with a 327 in it. Like I say I don't need a new motor as my 307 in the truck is currently running well with no issues, I'm just keeping an eye out and if I happen to find the right 327 motor that matches my truck then I would be interested. Also I will keep that in mind about the 307 engine mounting blocks. Bruce where did you find the information about the engine stamping codes and what they decode to?