okay i have a TOM bridge on my guitar and i was changing the strings and so my genius friend took the bridge and stop piece off and now im kinda stuck because i dont know how close to the body it should be, HELP!
hmm well the stop peice is usually held on by the tension. This happened to me and i put it back on i dont think it matters how low or high
Legend LP
Nylon Acoustic
Legend 10D Amp
Korg AX3G

It does matter, quite a bit actually. The stop piece needs to be adjusted so that the break angle of the strings is correct. That's the angle that the bits of strings are at between the stop piece and bridge. Too shallow, and you will have lousy tuning stability and sustain. Too steep and you run the risk of cutting the strings and constantly breaking them. As long as the posts for both the bridge and stop piece weren't turned, both pieces will go back on in the same position. Each is adjustable up/down. Set the bridge height so that you have good action without any fret buzz, and set the stop piece so that the break angle is approx. 45degrees to the main portion of the string, maybe a little less.
Once you get it back to where you want it, next time you change strings, leave one string in place while you do the others, then do that one last. I usually leave either the D or G string on, swap out all the others, then change out that one last.