I've got a '66 and '68 Chevelle Conv. The '68 is at my other house right now, but I'll take a couple pictures for you of those wedges; I'll also snap some of the '66. Some of them use a brass wedge on one side and a plastic on the other. Some use a brass one and a chrome one; I don't know which style your car uses. I have two sets, do you know which kind you need?
It probably goes without saying, but the only way you can align the doors on a convertible is while the car is on the ground on all four wheels.