Removal of E30 models includes removing the screws and the plugs over the screens, pulling out the assembly, taking off the cover over the bulb, squeezing together a clip holding it and pulling out of the assembly, separating wiring from it, connecting wires to it and replacing its bulb, fitting in both top cover and lens light then fitting screws afterwards. On E36 models press a clip that is reachable from an upper opening next to light assembly turn bulb cover anticlockwise to remove it release bulb spring and pull out bulb. To do this you must use plastic fuse puller which is already provided in your fuse panel for removing them check that filament inside isn't broken if yes replace with new one put in new lamp then replace clip on lens adjusting taillight if necessary lastly press into position. When we talk about installing aftermarket lighting on your vehicle there are things you should consider; first being checking their legalities for road usage after which unplug negative cable of battery and also unpacking a lighting kit choosing location lights appear to be mounted drilling necessary hole(s) mount these lamps install engine compartment relay connect wires coming from relay through good ground source fog/driving lamps light switch battery finding suitable place where switch should be mounted other end attached constant power supply turning them ON re-checking pattern when needed.