This is a really neat detail that not to many people know about. There are two styles of long rib cases. The serial number boss on 42, 43 and some 44s have a recess at the bottom of the pad where it meets the radius of the case. Here is a picture of the front of the pad
and here is a pic of the back. The casting is different on the cylinder base area as well. I will post another pic in a bit.
my dad got the flywheel bearings set, and the end play sorted out. Time to prep for final assembly!!!!
We spot face the bosses where the case studs nuts go. they get kind of worn down after 50 to 70 years of getting rebuilt
OHHH AHHHH shiny! The next step after all the bosses are spot faced is to do one more wash in solvent and water ane prep for final assembly.