You can apply an enamel paint over a lacquer, but NOT a lacquer over an enamel-- the solvents in lacquers are "hotter" (evaporate faster because they're much more powerful solvents) than those used in enamels (which use "cooler", slower-evaporating solvents). Thus once the lacquer is fully cured, an enamel clear or secondary color coats can be applied over them with little/no risk, while applying a lacquer top-coat over an enamel substrate will almost always end up badly with the enamel re-dissolving from the lacquer's solvents and "alligatoring" the finish... Requiring all of it be cleaned off and start from scratch.
Yes, there is a lot of ambiguity in paints and stuff nowdays... in the old days, it was easy to tell a lacquer and an enamel apart, and they were pretty much 100% labeled as one or the other. Nowdays, I've found several different paints that NOWHERE on the can did it specifically tell the formulation of the paint. I had to "infer" it based on the recoat windows and drying times. Generally speaking, if it says "recoat within 30 minutes (or thereabouts) or after 24 hours (or thereabouts)" and "fully cured in 48 hours (or thereabouts) or 1 week (again thereabouts)", it's an ENAMEL. If it says "recoat anytime, fully cured in 24 hours" it's a LACQUER. USUALLY lacquers are labeled as such on the can, where enamels (being the standard paint now due to VOC regulations) often-times aren't labeled specifically as such anymore. The changes in formulations and materials used to make the different "sub-brands" (like "Painter's Touch, Fusion, etc." within a specific brand) further muddy the waters and blur the line between basic enamels and lacquers...
The main thing to remember is, IF IN DOUBT, ALWAYS DO A PAINT TEST! Better to find out that a chosen combination of materials will screw up badly during a paint test than on the final rocket...
BTW, Rustoleum and Duplicolor sell BOTH lacquer and enamel formulations, so BE CAREFUL-- just because the primer, paint, and clear are a given brand DOES NOT mean that they're compatible...
Good luck! OL JR