I recently bought a MX1800. Mechanically ok, but had electrical issues. Got most of them all worked out thanks to the help of the service manual. Looks like I have an issue that points to the fuel level sensor. Got to remove a lot of stuff to remove it from the fuel tank. Question, the manual just says to remove the "lowering speed adjusting knob" and the "cutting height adjusting dial knob." I didn't find anything that eluded to how to remove them. I don't find a set screw or anyting else to release it and I've tried just unscrewing it to no avail. I'm trying to remove them without breaking anything. Anyone have any experience of removeing them?