In the 80's most of the paints were enamel based, but there were base coat/clear coat systems. (BC/CC)
A good way to tell...when you wax or polish the bike, does any color come off onto your polishing mitt? If so, then you have an enamel. Lacquer paints would probably start to craze after this time period, crazing being like micro-checking or looks like crow's feet.
If I had to guess from my past bikes, I would say that they are probably BC/CC because I never remember getting color off any of my older (80's) bikes.