I have a Sunburst in my collection who looks great. A few days ago, when I was adding risers to my curio cabinet, he felt the slightest bit tacky. I'm afraid he's about to turn bad. I'm guessing early onset plasticizer leakage. With other ponies I've found or gotten in lots that were already affected, I've wiped with alcohol.
Would you do this with Sunburst? He looks amazing and I hate for him to start breaking down. But I do know sadly that these are 30-35-ish year old toys and they won't live forever.
On a side note, I had a Sprinkles the cat whose leakage was so bad, his paint was coming off. I had to just scrub everything off; stripes, eyes, whiskers, the works. Broke my heart, but I'll try to repaint him one day.