How far over 80 are you? With fenders I'm at 82 1/4", which technically requires the front lights AND lights on the fenders. But I'm a rebel and only installed the side markers and the tail lights. Also, none of my lights have built in reflectors, so technically I'm pretty far out of compliance.
I'm going into the fourth season on the road and have never had anyone question the lighting (or lack of reflectors). I was even pulled over for doing 37 in a 25, and the cop didnt say a word about my Maine plates (I live in PA). People see our campers are are overwhelmed with so many other questions ("you actually sleep in that?") that they don't think about the nitty gritty technical mumbo jumbo.
If you're close to 80, I would REALLY doubt anyone will bother you. If you need to get an initial inspection, slip the guy an extra $20.
For everyone's reference, NHTSB info is here:
https://one.nhtsa.gov/cars/rules/standa ... rpstr.htmlAnd eTrailer has a great write-up here:
https://www.etrailer.com/faq-trailer-li ... tions.aspx