So finally the case was empty. Time to take the jugs to the machinist and see what was what. I found a little speed shop in Essex, Md that worked on everything from Ford flatheads to Willys jeeps to Mercury outboards. They had never heard of Urals, let alone IMZs, but they seemed interested in something different, so I made plans to bring the parts by.
I had a set of one over OEM pistons in my parts cache. They were covered in preservative Cosmoline, an evil, rank mixture of oil, grease, and wax, then wrapped in wax paper. This stuff reeks and is a chore to get off, even with gas.
They already had rings installed, and I had a set of new gudgeon pins in another glob of Cosmoline.
The pair I had were P1s, which evidently signifies they are the first over diameter. "P1-78.15"mm.
My cylinders measured 78mm at the outside, as deep in as my cheapo calipers could reach, so I was hoping I could use these pistons and save some dough.
So, I packed everything up and carted it over to the machinist.
Time to see how bad off the transmission is.