Installing driving lights – 99 LS, 4x4, 4DR, 4.3

Just bought a pair of driving lights and have a few questions before I start to wire them. Where’s the most common place to mount the relay? Where’s the most common place to tap into a battery hot wire, and to tap into a parking light wire (what color too)? And where’s the best place to route the on/off switch wire thru the firewall? I guess I should ask about the grounds too but I thought I could probably figure that one out myself.

Also, legally, these can only be on when lo-beams are on so I assume that wherever you tell me to tap into the parking lights will ensure that. Was that a question? Anyway, I want to make sure they’re legal, and don’t come on with the day time running lights too.

Thanks,
Deadeye