I dunno if I posted this before, but I have been annoyed at the dim dome lights (and luggage area light on my wagon) of our 2 remaining Volvos for awhile, and ordered some 'warm white' LED 'festoon' bulbs the right size from superbrightleds.com ... and WOW what a difference.

this bulb specifically fits both 740/940 and 240 dome lights. there's at least two lengths for Festoons, you need the 42mm kind, like...
6451 LED Bulb - 6 SMD LED Festoon | Festoon Base Bulbs | LED Car Bulbs | Super Bright LEDs

I got warm white for the main dome, and a red one for the trunk light (I do amateur astronomy and often use my trunk as a sort of desk, for my charts and accessories) ... the red one is really bright red.

I also replaced the 'reading lights' on the 740's dome with these... they also are brighter than the stock bulbs, but not as much so as the festoon above, and sadly are only available in cool white, not warm, so they somewhat contrast.
194 LED Bulb - 1 SMD LED Wedge Base | Miniature Wedge Base LEDs | LED Car Bulbs | Super Bright LEDs

still, a big improvement.

 

cool white....would be my choice....it is a brighter or clearer light correct?

I don't like dim lights i like bright as hell....so I can see a written address on a paper or whatever...I got bad vision...i am referring to the dome light.

 

the cool white ones are harsh-blue-white and look obviously like an LED light, the warm white ones look more natural to me, like a much-brighter version of the original light. both are nearly the same effective brightness.

 

Oh, I see, well the price is good for a good upgrade as the OE lights are not so great.