I've got a couple of 54" cylinders I need to shorten to about 40" (compressed). Anyone have some pointers or "watch" items they'd like to give? Do these types of cylinders have a "stop" in the bottom? (To keep the piston away from the weld area.) I should be able to extend the piston and keep it cool during re-weld. The system is 2000psi and the cylinders only 2". These are going on a small tractor front-end loader I'm building.