dont bother with clear coat, just get yourself some polishing compound, some 1500-2000g sand paper and a small orbital buffer. it will come out much better than clear coat. you have 2 options to shine out tail lights, one being clear coat, the other being just polishing, or even a combination of both. but what most people dont realize is that just using clear coat, isnt going to get rid of all the orange peel. if you want them to finish out correctly, you gotta treat em like paint, where the quality of the job is 99% in the wet sanding.
granted, on those i posted above, i used a 7" variable speed polisher