No not a machinist, I was Chief Engineer at an Aircraft repair and maintenance facility. I started out in the bush working on Beavers, Otters, 185s, Norseman. Beach 18s, DC3s. Then worked for two schedule and charter airlines, more turbine powered aircraft and helicopters, then a few jet propelled aircraft. While visiting my Folks on Pender Island, I was offered the Chief Engineer position. I phoned my girlfriend in La Ronge, who told me it was 49 below zero there, it was 49 above here, easy decision. Not a profitable career change, but I wasn't freezing my [censored] every winter. Now I have a sawmill business.
The small journal engines didn't have the same problems with the eccentric rear seal groove as the large journal engines did. Yes, yours had a two piece robe seal but I would use the BOP two piece chevron seal. There is a rope seal remover and installation tool to pull the rope seals and reinstall with the crank still in the block, but I have more faith in the BOP seal.