I recently brought a ford LSD center and 3.9 diff gears; I've heard that you can tighten up the LSD by putting shims in it. Is that right; is it a hard job to do? And how would it be done??

thanks,
Dan

pull it apart and you wiil see and better understand how they work im not sure about shims but you can get stronger springs witch work well .... just remember crown wheel bolt are left hand thread and when pulling apart

The shims sit beneath the springs. They just increase the clamping pressure. Cheap and nasty, but it can work. better off getting new springs regardless. Old ones eventually lose their tension and reset