Hey guys I'm getting ready to install my Ford Racing speedo recal I got from American Muscle, and the instructions it came with are decent enough since I do have some automotive knowledge, but I was just wonderign if anyone has installed one of these and come across any issues I should look out for? I plan on doing the underhood install, so where is the best place for the ground? Someone mentioned running it all the way to the battery negative terminal? One final question, I installed 4:10 gears in my mustang 6 years ago, and I cannot remember what my stock gears were. Is there anyway to tell if they were 2:73 or 3:27? I've looked online and it seems to be a 50/50 split of both. Thanks!