In my 2004 A8 D3 they are all capless filament bulbs.
That is the two boot interior lights, one in the trunk lid and in each door there are two (one puddle light and one door open light in a red holder)
I have experimented with LED replacements but PLEASE do not use "canbus" leds in any of these fittings, the resistor can become so hot that the led melts and heat is conducted along the supply wires melting the insulation and causing shorts. I was very lucky with mine, spotted it in time to save the car.
