Have installed the side marker lights, but they aren't yet functional.

Mine has the pre-wired harness plugged into dummy slots on both ends.

But the instructions at IPD and elsewhere appear to be for those who need to splice wiring to make them work.

No one addresses my situation- where does the front connector go? Does it simply plug in somewhere, or do I need to splice as well?

It's been a while...

Does your dummy plug behind the headlight also have prongs? If so, they connect up to the turn signal/side marker lights in piggy back fashion.

Klaus
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Proud owner of a 220S. If I had more room, I would have more Volvos.

No, the dummy plug is just plastic. Actually have two unused harnesses there, both with plastic plugs, assume one is for fog lights, which I don't have?

Still not sure how to hook these side markers up, doesn't seem like I need to splice. Would like to avoid that if possible.

I found this criptic on IPD's web site:
If your Volvo is pre-wired you’ll be able to see the black plastic loom running alongside the inner body. Two wires are wrapped in the plastic loom and are about the diameter of a pencil. The wire comes up from the front of the car and passes the hole in the fender to a rubber grommet in the body where it is plugged into for storage. The grommet is located about 3 inches to the right of the opening in the driver side fender and up about one inch. Use a flashlight if it is not readily visible. You will not be able to reach it, however the plug can easily be removed from the grommet by gently pulling on the wire. Use a coat hanger to fish the wire out through the hole in the fender. Make a hook on one end small enough to fit through the fender hole and large enough to hook the wire. Use the tool to catch the wire and pull it through the hole in the fender. Plug the wire into the lamp and snap the lamp into the fender.
The lamp will only go in one way (small end toward the front of the car). Pre- wired cars will flash in sync with the turn signals whenever the turn signal or emergency flashers are activated.

Call them just after 10am Pacific time zone, and they will be glad to help you. Really nice guys!

Klaus
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Proud owner of a 220S. If I had more room, I would have more Volvos.

Yes, it only addresses plugging in the marker into the fender, not what to do at the other end if your car is already pre-wired. Thanks for checking into it.

I didn't remove the dummy plug, but I suspect you are right, that's the only explanation that would make sense. Thanks, will take another look.