Hello all. I've picked up a nice Poulan 4000 that has a scored piston. The jug appears good and only has one very slight ridge that I can catch with my nail. I will use sandpaper and muriatic acid to try and bring the ridge down as much as possible. I also may have located a damaged 4000 that has a good top end. If not, I will need a piston. This is my first venture into a Poulan Countervibe top end, so do any of you have recommendations for a replacement or source for a NOS piston? Yes, tall order I know. Lastly, what about a/the tool to remove the piston from the rod? This looks like a bear and I wanted to ask before I try anything. I saw where some members have made them in the past, but I don't believe I have that skill. Thanks for your input and recommendations, and enjoy your Memorial Day Holiday! Best, Max.