Only the INPUT voltage is able the change by re-wiring. 120AC or 220AC, or 277AC, yada yada yada. :dance:

No, you can't change bulb wattages. You'd have to change the whole ballast and put it in your old case. Same with HPS or MH, you need two different ballasts OR a switchable electronic "digital" ballast. :thumbsup:

1000bulbs.com has new ballasts as well as millions of bulbs. :clap: