The last job to complete my PE400T restoration, is to make new shocks.
There are some flaws in the original design (gland bushing runs "dry" - above the oil seal, and the rod seizes / bends, floating gas piston jams, etc). There are several replacement shock options, but none look like the originals.
I have made new bodies, glands (removable; retained by internal clip), gas pistons, added nitrogen charging valve, used Kayaba seals, etc.
My dear, clever friend Robert designed and built a robotic welder, and the first job he used it for yesterday was to TIG weld the mounting eye (base) to the bottom of the barrel. I also have a PE175, so he welded two sets of barrels. 8 weeks to build the machine, 2 minutes to perfectly weld 4 shock bodies.
Richard