04 dodge ram parking lights

I was looking at this wiring diagram for a 2004 Dodge Ram and it says I can grab the (+) parking light at the bulb. Is this possible? I already have to run a tach wire out there so its not a problem running an extra wire under the hood. I'd rather use a (+) parking light wire rather than the (-) inside the cab because the one inside the cab requires an extra relay and resistors. This is my brother's truck and I'd rather keep the relays under the dash to a minimum.. He was extremely disappointed with the alarm system a rinky dink audio shop installed. There were relays everywhere and all of them t-tapped into the constant ignition wire....yes...t-taps One last question. What type of solder do you guys use and does the type make a difference? I use Radioshack 60/40 rosin core solder. Pic of the truck just for fun :)

There is a harness on the left side of the column, find a WHITE/ gray for (POS)+ lights.