johntank wrote:
I think I would take the C by a propane dealer/supplier and have them check the tank to see what needs to be done or if you need a complete replacement tank. JMHO
This seems like very good advice to me, as well. If you can just replace the valve (or not—they aren't really designed to be left in positions between fully open and fully closed) and paint the tank and be safe, there's no need to do anything more. Maybe they would recommend inspecting the interior of it or something along those lines; I'm not a propane specialist by a very long stretch.
You do have to have the tank empty to replace the valve, but then again you need to empty the tank to replace the tank, so there's not much difference there.
Many propane tanks are in safe regular use that are older than 25 years old.