I always wax the hood after prep before putting down a clear bra. My first job was about 1.5 years ago and there have not been any issues with the edges lifting. Obviously make sure all the solvent has left the wax/sealant before bra application. I started doing this because I read that it's a worthwhile preventative measure to protect the paint. I don't know how necessary it is, or how often damage actually occurs under a clear bra. It may help a little with the install by aiding lubrication, not sure because I always do it. And yes, a VERY clean environment is needed on light paint and absolutely do not try it in the sun!