Here's a link to a cab mounting kit for 55-59 cabs. This is the one I got to put my cab back on. It has bolt and nut sets for the fron and rear of the cab. When I first dis-assembled my truck this is what the factory set looked like.
I've had 2 different cabs at one time and neither one had caged nuts for the cab mounts.
Kim
http://www.brotherstrucks.com/prodin...number=CMS5559