To me, late 79-80' models with non epoxy preamps are the best sounding stingrays ....and the most reliable in terms of electronics.
I had a lot pre ernies, I sold all those before 79' ....I saw some odd electronics on these basses, Leo was making a lot of experiments, with 5 different
kind of electronics from 1976 to 1980.....
By the way , I will sell 1-2 79' models , a black alder and a naturals ash fretless one