GM used lacquer on many auto & truck lines through the early 90's. Others with more paint experience can chime in, but I believe the Caprice didn't get BC/CC until 91.
I'm fairly certain you can touch-up your OEM lacquer with enamel or urethane without a problem. Its when you use lacquer on enamel when you get wrinkling and adhesion issues due to the solvents in lacquer.
If you'd like to get the code to shop for touch-up paint, you can find it on the RPO code sticker located in your trunk.
https://www.dropbox.com/s/uuzreucpoa8jkg2/White%2087%20RPO%20Codes.jpg?dl=0Not to discourage the do-it-yourself nature of this group, but if you have nice original paint and just need some color blown onto some spots or a panel here & there, I'd let the pros deal with it. Any good body shop should be able to get your Caprice back to where you'd like it and keep the rust away. Hope this helps. I'm sure that's a nice driving car!
How bad do you think the rust under the top is?