I had some PPG Deltron left from 1989 that was still usable last summer. The hardener had gone bad, but I discovered I could use common hardener made for urethane paint today just as well. Try it first, but you may be surprised to find it is okay. This Deltron had been stored in the garage since 1989...hot, cold, whatever. I had black, white, clear left from a 1957 Bel-Air I painted. 1.3 tip is pretty small, however. As Kevin said, you'll probably need to cut it a bit more than normal.
