I have two sets of Euroheadlights.

My first set, the cheaper "JBAuto" brand from Bram in the Netherlands, will probably best serve as an example you can use in your case. These sockets did not have any wiring for DRLs, but the back (outside) of the socket had a dimple to show the correct position for the second terminal -- I just drilled through to the inside of the socket, forming a passage for the DRL's wire. Then I bought a generic replacement socket that included the pigtail leads and metal contacts for a bulb's base (from an autoparts store), dismantled it, and inserted that lead through the hole I made in the Euro's socket -- this added pigtail was my contact for the DRL. Haven't had any problems with this.

I hope this helped.


BTW, my second set of Euroheadlights is not as useful an example for you problem. They're actual Volvo-Cibie lamps, and included the wiring for the DRLs. But it's worth pointing out to readers that they were originally wired in a way that might seem peculiar, in that they use the DRL circuit's ground as one of the socket's hot leads....
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It's sort of like using the side-fender blinkers as lights-always-on, but they blink 180 deg out of phase with the turn signals also by grounding them to the other bulbs hot wire. In the case of the DRLs, I think it was just an easy way to be sure that they're off when the parking lights are on -- that would produce +12v on both sides, and no current would flow through the bulb.
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This, of course, is of no consequence when using incandescents because they're not affected by polarity. But if anyone is considering installing LEDs of any kind (either the commercial LED-substitute bulb or emulating my "project"), they would not work with the OEM DRL wiring unless the wires are rerouted -- cut and splice them suitably so all the colored wires are "hot" and only the black wire is the ground.