How do I rebuild a cadillac trunk motor?

The trunk on my 1993 Cadillac Sedan Deville will not close, somone told me that instead of purchasing one from a junkyard I can rebulid the one that is presently on my car.|||Trunk locks (and motors) are hard to find now. I looked for someone else awhile ago. If you are lucky maybe you can find one in a junkyard but it is a tough road.