RE: Who is converting Toro trimmers?
Go on ebay for a laser tach. They are used for things other than planes. You put a piece of reflective tape on the back of the prop for it to read. They are very accurate. They run around $50 on ebay. I bought one because I usually test run in my workshop and light is a big issue with the regular tachs. This one will read in total darkness. It does however have trouble in bright sunlight. Then a regular airplane tach works well. I just got sick of getting bad readings in less than perfect light conditions with my airplane tach.