Brad is correct in that there are different thickness spring rubbers in both the front and back. The rear camber can be affected by the weight of the hardtop, spare tire, and even a full tank of fuel. Then add heavy luggage and watch the negative camber take over. It's one of the design flaws of the cantilever suspension. If you have a Big Blue Book, there is a chart that shows the thickness of the pad according to the color markings on the springs. That assumes that no one has touched the springs or spring rubbers in nearly half a century. So you get to guess. I recently priced the pads from the dealer and the cost of each side was upwards of $120. Yikes!
So, if you have a hardtop on, spare in, and a full tank of fuel, and still have too much positive camber, the "proper" fix is a thinner pad. Well, how do you know the thickness you have and how thin to go? What other folks and I have done was buy the thinnest pad and, if it was too thin (negative camber), shimmed it with some $5 flange gaskets from McMaster-Carr. Look for posts from Jim Villers on the topic. I think he gives the part number. You get 6 gaskets for about 5 bucks.
This works to adjust the ride height up front too but those springs are significantly harder to remove and replace.