This has nothing to do with the USAC rules and everything to do with the rules of your local velodrome. There is no way in hell that Trexlertown is going to let you out there with an old converted Trek, but I imagine that Kissena is a little more relaxed about these things, given the shallow banking.
Really though, if you want to race track, get a track bike. A Kilo TT will do you just fine, and costs as much as most conversions.