If you don't cut the ridge, and you beat the piston out, something is going to break. That something might be you block. Flatheads are sometimes fragile in this area. I saw a guy do this, and cracked one cylinder, and broke the top out of another. This was after I advised him to first cut the ridge. I saw another guy weld nuts on the studs, and use an impact gun to move the studs. he broke a big chunk out of the block. If you don't believe me, ask the top flathead builders on here. Like Dale, or Tardel.... Not trying to be a smart *** here, just trying to save you some grief......
Why take the piston out at the top? Just dis***emble the rod and push it down. Plenty of room for that.
Thomas stated he was going to take it to a builder. I would suggest take the motor out whole and let the builder take it apart.
Only four pistons will come out the bottom, #1 #3 #5 & #8 you,re in luck with #5, but you'll have to pull the crank!
It's also a "pull rod" during the Intake stroke. On the Compression, Combustion and Exhaust strokes it is pushing on either the piston or the crank. I apologize for being a smart ***. I was born this way.....
Stay away from champions. You may be ok for now, But at least you can save some money for a rebuild. It’ll happen sooner than you think. There’s a reason why your plugs are fouling ya know.