Medyo matagal na itong thread so for posterity na lang.

I tried this method on both my cars, 8 and 15 year old car. yun 15yo ko is yellow all the way, tipong akala mo pang need to replace na, as in hindi mo na makikita yun bulb sa loob or yun mga shiny things inside.

#1 Pre-soak in water 220 to 300's, 1000 to 1500 and 2500 to 3000 grit sand paper (3 types of grit in total)
#2 Spray bottle with water or h20 + car shampoo mixture

1. Clean headlights (I use water w/ car shampoo in it) towel to dry
2. Feel the headlights with your fingers para malaman mo gaano kagaspang
3. Wet sand using 220 grit in a horizontal direction (press firmly but not hard), wipe with towel to see if the yellow haze disappears
(Do not sand it dry always keep the surface of the headlights wet. Headlights will be all blurred up by this time if dry)
4. Wet sand with 1000 to 1500 grit in vertical motion naman (HL will get a little clearer when wet but still blurred when dry)
5. Wet sand with 2500 to 3000 grit horizontally again. Can't find 3k so 2.5k lang gamit ko on both my cars. (HL is more clearer when wet but still blurred when dry) towel and dry your HL thoroughly.
6. I use Black and Decker KP600 polishing machine, I pour 5 drops (parang sa dice) onto the polishing wool then spread it on half the headlights first before turning on the polisher
7. Polish using mother's headlight restoration polish (not the kit) or same kind on half muna in a slow motion (it did not make a burn mark on my HL naman kasi 4400rpm lang kp600) Do not stay too long on one spot para sure hindi magka burn marks
8. Polish the other half naman using the same method as above. Wipe off residue

I repeat 7 & 8 3x each or up to kung saan ka satisfied.

9. I applied turtle wax same as what I use sa body ng car onto the HL's then polish with machine then wipe-off residue
That's it, HL's looks brand new na.

Nabasa ko para hindi daw manilaw kaagad.

Few light scratches from "wear and tear" are now visible kasi heavily oxidized HL's ko kaya natakpan, hindi iyan dahil sa liha kasi iilang areas lang may ganun, kung sa liha iyan eh dapt buong HL ko meron. Pero very light and barely noticeable sa 8yo car ko, talagang magkakaroon niyan kasi luma na kotse.

This method still beats the free headlight buffing I got last nov 2013 by availing of ther 4 steps exterior with interior detailing, no wet sanding just buffed with something they just said "special formulation" daw. Sobrang visible scratches then ang gaspang ng HL ko. Good luck on your diy headlight restoration!