Stop start stop.

With the new seal I had little trouble getting the crank in, crank out of the freezer, case and bearing warmed up with a heat gun, it was a snug fit but I could do it with my hands, happy with that. I went on to get the cases ready to put back together, all the gears and the kick start mechanism in, the fly seal in place, a light coating of loctite gasket sealer on both cases to be sure and the gasket in place, I was right to go so I heated the case just to assist and as I lightly tapped away I was getting excited but, why is there always a fking but....I'm not sure if it was my fault or whether it was the wrong size but the fly side oil seal rubber began to bulge out is it got close to home, WTF.
I took the cases apart to have a look and the little spring was damaged and the rubber had split. so after a quick measure up and a dry run with the seal alone, it appeared too small to go over the final collar of the crank shaft without damaging it??
Does the Malossi crank have a special size seal or did I just do the installation wrong, It might work better if I put the seal in place on the crank before I install the case?? SO it's back to the drawing board until I find out whats going on.
Tonight will be the clutch's turn for a re-build.