refinishing headlamps - what pad and compound to use after wetsanding?

I have refinished headlamps for years now, by using 400/800/1200/1500/2000 grit wetsanding, then finishing off with a wool pad on a drill with a 3M compound. I have burnt lenses many times with this wool pad and was never too good at it.

Can anyone advise the proper finishing compound and proper pads to use? I recently got a porter cable DA that I would use instead of a drill. Also is there any sealant I should use after compounding?

Thanks