Get some E-code (European spec) H4 bulb H6024 housings. There's a guy on Ebay that sells Autopal (an average Euro brand) for about 40 bucks a pair shipped. I have sets of the square H6054 style Autopals in most of my vehicles, and a set of H6024 style housings in a Wrangler.

It gets you two things, H4 bulb technology, and E-code optical specs... Basically DOT has no real specs for output quality (only wattage limits) the Europeans however have minimum standards for actual quality of the output. Any E-code light has to be good enough to be in a car going unlimited speeds down the Autobahn... So their standards are far better than ours.

E-codes have a sharp horzontal cutoff, excellent coverage without hot spots or blotchyness.... very even smooth output and 3 to 4x better output while actually being nicer to opposing traffic due to the sharp cutoff.

Pet subject of mine...

BTW Blow By I found this looking for pics of that bad ass Willy's of yours. I am a Jeep nut and thinking of putting a Nailhead I have into one. Hows the head room with a 3" chop?