After spraying a base coat do I really only have 30-45 min. to spray the clear coat?
No, you can apply the clear much later if you like. There seems to be a difference of opinion on the maximum time frame; I’ve heard anything from 72 hours to infinity. I asked the Dupont techs on their tech line, and they don’t seem to know either, and it isn’t listed in the technical manual. I’ve done it three days later with no apparent ill effects.