I wanted a vintage Tach/Dwell meter so I bought two Sun Model GA Tach/Dwell meters off ebay. The idea is that I can restore one out of the two. Good thing I did as one of the units has a dwell meter that is beyond repair. So, I also bought a Sun manual that contains schematics, calibrate, and other info to help get this done. First off will be to document the units before any work is done. I do this by taking lots of pictures. I also use the Antique Radio Forum ( https://www.antiqueradios.com/forums/index.php )for getting info and advice. I am in the process stripping cabinet paint and repainting with period correct blue paint. Also selecting parts from Digikey ( https://www.digikey.com/ ). I plan to re-stuff all the capacitors like I usually do when I restore radios.