right i cant remember what its called for the life of me, but as soon as i remember ill let you know.
its a thread release spray similar to wd40 but a shit load more expensive. white can with a red lid and red writing, got it from bunnings right next to wd 40.
spray it on your lights for a few minutes, then give her a good old scrub, repeat until shiny!
if it fks your lights dont blame me. but mine look like new!
there you go 20 bucks 10 mins. all good.