somewhere there is a big red round relay thing that is responsible for a lot of grief in Volvo's and I believe there is a wire you can clip and get rid of those silly dashboard warnings. black tape can work too , or remove the bulb. After that just look when you drive at night and check your bulbs by the reflection in nearby windows.

Volvo made pretty safe cars, with the exception of the tail light wiring. i converted my 240 to normal bulb holders. The silly printed circuit board connections were an example of really terrible engineering. It seemed to get worse with even thinner PCB traces as time went on. often the problem is the spring loaded contact on the bulb holder isnt; making a good contact and to fix that you need to replace the PCB, or replace the sockets with better ones that don't fail so often. if you remove the bulb and replace it , often the PCB board won't make contact because it is very poorly engineered. the clips get bent up and the very thin traces on the PCB board were cheapened down to the point of them being an issue for almost every Volvo. in my 740 wagon the bulbs are also in a place where there is not enough room for human hand to fit to install the connectors and they need ot fit in a certain way.

If you do remove them , first mark the top of each so you know the correct orientation when putting them back. like the bulbs they push in and turn a bit.

if you look at your headlights you should see basically a tin plate that is mounted to the inner fender. You might remove the airbox for room. I had a dim drivers side headlight in my 740 due to bad grounds right there. a bad ground increases the circuit resistance.

in some cars you will find there is actually an unused tail lamp. It was used in Europe. If you want you can add a bulb holder and fill that unused tail lamp socket. make it an extra brake light or a signal light.

the OEM alternator can handle original style bulbs. lots of people add LED's and don't add the resistor, then you see cars with headlights that flash and flicker, which is extremely annoying. blinding oncoming traffic is unsafe too.

If you want more light I'd just add OEM style non LED driving lights, the car should be fitted with wiring for them. Not everyone bought the option but I think it was always fitted in the wiring harness. you might find an empty connector up around the headlights that was intended for that.