Thanks for the helpful comments. I plan to run the motor a bit after it is placed back in the frame, just to be sure there are no leaks or other problems, before proceeding with replacing the cab. I promise I will do the compression check correctly,(after adjusting the valves). This is what is so fun about this hobby, you learn so much (and I started from about zero knowledge).
I suspect that the rebuilder was some sort of established firm. A shade tree mechanic would not have bothered to overstamp the serial number with another number. They had to retain the old valve cover because a more modern 235 would have the oil filler/breather and it would be too tall to fit under the floor cover (doghouse).
Kent
