rear shims ?
The stainless shims you can buy have one slotted end that's designed to fit over the trailing arm bolt. The other end has a hole for the cotter pin that holds the shins into the frame pocket. You don't have to remove the bolt to install them, just loosen it and pound them in. You really should have an alignment shop do this so they can set the rear toe and align it with the proper number of shims on each side of the trailing arm.
Shannon
As sb69coupe says, the shims have slots so all you have to do is loosen the trailing arm bolt and slide them in. Using stainless steel shims is a good idea because of rust. Be sure to get the long cotter key that holds the shims in place.
I have included this link to C3 FAQ. There are several links to alignment information.
http://www.corvettefaq.com/susp.asp
The Van Steel 1963-82 suspension video shows how to do a quick alignment so that you can get to your alignment shop.
Some OEM shims were not slotted... they had a hole in each end, and could only be removed or installed by removing the through bolt. I have a bunch of these, brand new, with the GM part number stickers still on them.
Tom (Shannons friend) guilt by association. :)











