Hi,
If your racks are from 1994 or newer they will not have the number on the out side.  If you have the raingutter towers you can open them with a big flat head and a hammer buy turning the lock untill that little screw on the side closes in allowing you to spin the handle again. Then just get some new handles and locks. If you need any of those parts let me know I have some laying around here.
Good luck
Kevin
www.rackwarehouse.com
81 Vanagon