Hello guys, I just purchased a Cobra Trackside truer, for my touring and pan car tires...I also purchased the carbide bit to help with cutting the tires... My question is what is the best way to actually true tires down? This truer has no measuring device on it so I am not sure how to tell how much will be getting cut off each pass...Any help with this matter would greatly be appretiated...Also what is the best way to get rid of square edges, someone told me that using sand paper on the tire edge would work, but I am unsure how to do this without taking too much off... Thanks Jeff