Interior Lights wiring question

I'm adding some footwell LEDs and instead of wiring them to the footwell light bulb, I want to tie them into the interior/ Dome light circuit so I can turn them on/off.

I tracked down the wiring but now I'm more confused. According to my meter, the grey wire going to the dome lights is always hot- makes sense as you can turn them on at the light.

When the switch next to driver's left knee is ON, the pink wire has no current. When the switch is OFF, the pink wire is 12v+.

I've never dealt with this. Anyone know how to wire the footwell lights up to the dome light circuit?

 

I did think about that, but I want the interior footwells to be independent of the exterior cargo. I may end up using a switch and a relay with the OEM footwell light as the trigger.