"A question for Ray: When you made your stainless heat riser shaft, what did you use to cut the slot where the spring hooks up?"
Joe,
I wish I could remember but that was about 35 years ago and my 73 year old brain is not so reliable any more on details like that. I may have used a slitting saw and my milling machine but a hand held hacksaw could do the job well also.
The stainless steel shaft and manifold bushings cured a chronic sticking problem that I and others were having and no amount of heat riser lube permanently cured it. In any event, in 35 or so years the sticking problem has never returned so it's definitely "problem solved". Others on this forum suggest a hammer as the proper tool to free stuck hear riser valves but I prefer finesse to brutality and I can enthusiastically recommend the stainless parts. If stainless round bars are not readily available to you the parts can be made from hardware store stainless bolts.
If you have any other questions give a shout.