HI Carnage, it sounds like your problem was what is called "bleeding" where the paint creeps under the tape. The members have made some great suggestions, and the best thing you could do is try a few of them and see what you like. As for my opinion, I don't care for canopies either, but it is a necessary evil.
Here's one other alternative that requires no masking: You can paint some decal film with first of all the interior color, and then the exterior. Then cut it into strips the same width of the framing on you model. Then you can apply it to the canopy and you are all done. And, the interior color will show from inside. The thing is, if your plane has a lot of curves to the canopy, it might not work.
Good luck!