I got tired of having to shim up whatever bolts I could find laying around the shop, so I measured our engine stands to see what bolts would fit and leave about an inch protruding, and bought grade 8 bolts that fit exactly, with only one washer under the head. I then put 4 at a time in plastic sandwich bags and labeled them "Ford" (7/16 inch) and Chevy (3/8 inch) and keep them in my tool box.

The other problem I would have when shimming up too long ones is that the too long part sticking out impaired the ability of the engine stand to rotate one direction. The part sticking out would hit the upright support. With bolts that are just the right length they clear fine and you can spin the motor completely over in both directions.

Don