Re: 1988 RG760DG Ibanez turning green!!!
It's pretty common for the clear coat on older Ibanez finishes to go yellow like that (the yellowing in this case making the grey look green). Most whites that have been exposed have turned yellow, I used to have a PGM30 that had turned pretty yellow, my Vinnie Moore model has a yellowed body, but the finish on the neck must have been different or sanded down a little, because it's still perfectly white. To me the worst that I've seen is a lot of DSY 550s that have turned from a bright yellow-green to a nasty orangish yellow from too much exposure to light.
The thing that's kind of a mystery here is that if you've cased it, it shouldn't be so bad I wouldn't think. My 550 DSY has been cased for most of the last 10 or 12 years after playing it out a lot the fist 5 or 6 years I had it, and it's color is still brilliant.