Headlight Swap Under Hood Switched Volts

[mustang90]

I have a set of raxiom headlights I'm installing on my 08. Instead of tapping into the parking lighst so the marker lights function when the headlights are turned on, I would rather have them tapped into a switched volts so they illuminate as soon as the car is turned on. My question is where is the best place to tap in and will I need to run a relay? The marker lights don't draw much power at all.