Is there a way I can make a set of passive pickups into active pickups?
No, you have to chage the pickups out.
apparently UG's only type O-

Quote by Strike9

Thanks jb_designs.
ummm there would still be passive but if your after a high out put (like in active PUs) try screwing your PUs up higher from the bracket. To do this you look at your guitar see the screws either side of the pickup tighten up to make the PU go up loosen them to make them go down
Quote by Ichimaru
Pics? I can tell if someone has AIDS just by looking.

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BTW, what's metal and full of holes?

Dimebag Darrell.