giving a litlle light on this subect
 

ok so im new to this crowd, ive been a regular on the 67-72 forum since 2007 and i just got me a nice little GMC Sonoma 1999.
my lights left something to be desired....or seen. so i did some upgrades
first i scrubbed the heck out of my lenses with paint rubbing compound, this scrubs that scummy yellow layer right off. polished the lenses with some polishing compound then waxed them. i waxed them because the wax provides uv protection. the uv rays are what makes the lights look crappy.
Next i installed new silverstar ultra bulbs. these are pretty bright but for their max potential i learned to install the relay kit so i ordered one off of ebay for 8 dollars, 12 gauge wire and good connection points.
all in all this only took me about an hour. i highly recommend the relay kit. it really brightened things up

Re: giving a litlle light on this subect
 

Done this on my 93, best thing I every did with the relays.

Re: giving a litlle light on this subect
 

I've tried the polishes and buff systems. The best lasted 3 months. Finally I decided to just replace lenses. Aftermarket ones are good and cheapish

Re: giving a litlle light on this subect
 

I actually work for an aftermarket crash parts supplier. I'm going to clear the OEM's next week and if they still fade I'm gonna replace them.