How to replace Corvette leaf spring mounting bushings/insulators?

I bought a used set of springs for my C5 sight-unseen and was disappointed when they arrived missing half the bushings on each. The seller explained that he had bought some aftermarket springs that came without bushings, so his mechanic cut the bushings off these (but only half, for some reason?) and used them to install his new springs. He apparently didn't know this wasn't a normal thing to do and was surprised that I considered it a problem. Anyway, it's a nice clean set of low-mileage springs, and instead of going through the trouble of shipping them back, I decided to keep them and try to make them work by reusing the bushings from my old springs.

The guy who removed them did a pretty clean job, but it seems like he cut through the very bottom of the rubber and left most of the adhesive on the spring. My best idea so far is to use a wire saw, like the kind you would remove a windshield with, to remove the bushings from my old springs, then re-attach them to these with 3M Window-weld urethane adhesive. If anyone has any other ideas on how to cleanly remove & re-attach these bushings, I'd love to hear them.

Here's a picture I took after cleaning off the remaining rubber with a razor blade, so you can see what I'm dealing with:

This was such a weird and specific question, I'm not surprised that I didn't get an answer, but since I just logged into my account again and noticed this old thread, I thought I'd let the world know, 4.5 years later, that I found a solution. I talked to a friend whose family has owned a dealership for years, and he gave me a killer tip: "Use a fish fillet knife." Apparently that was the preferred tool at the dealership for cleanly separating glued-together panels and trim. So, I went to my local Fleet Farm store and got the cheapest fillet knife they had, since I was planning on abusing it in the garage. It worked great! I cut the bushings off the old springs with the fillet knife, attached them to the new springs with windo-weld, and have put many happy miles on the car since then. It's come in handy on a couple other projects since then, too.

So if someone ever has the same weird problem and is searching on the internet for a solution, hopefully they find this thread.