Electrical Modifications
 

I'm thinking of modifying the system of the delayed dome light. First of all, I'd like to make it so that if any door is opened, then it will delay the light. After studying some wiring diagrams, it seems it shouldn't be too difficult. Any pointers you could give on this? Eventually I also intend to install an L.E.D lighting kit for the foot wells, and possibly somehow make the dome light an L.E.D.

I put LED dome lights in both our volvos, using lights from www.superbriteleds.com ...

specifically, this lamp is a drop in replacement for both front and rear dome lights in my 740 wagon. 6451 LED Bulb - 6 SMD LED Festoon | Festoon Base Bulbs | LED Car Bulbs | Super Bright LEDs

because I'm an amateur astronomer, I put a red one in my wagon's rear :) warm-white in the front. much MUCH brighter than the stock lights.

Interesting indeed! I bet it would be a lot nicer than the stock light. Still, think it'd be a difficult task to make it to where the light would do its delay with all other doors?

haven't had the energy to look up the diagrams yet.

Well, the timer relay is somewhere under the dash, (either under the instrument cluster, or the plastic side panel) on the driver's side. I think the only challenging parts would be routing all the wires from the door switches to the relay.

on my 740, its built into the dome light fixture