Decided to install a reversing camera on my A4 B6 Cabriolet. Didn't want to go for the OEM option which is costly (and probably isn't compatible with my head unit) and didn't like the look of the dodgy number plate bulb replacements because they all seem to reduce the light output and I suspect this is an instant MOT fail.

However, it did give me the inspiration for my own 'lazy' install. Using the front left hand side of the right number plate bulb holder, I drilled a 4.5mm hole which is worked slightly larger using a 5mm bit and then was able to screw in an off the shelf reversing camera. This has ensured the the light output is still exactly the same as normal but has provided a reasonably sleek install. You have to drill a hole through the casting behind. If you drill through the lower part left part (essentially perpendicular) rather than the back part then you can tuck the wires through really tidily and hide them away from the bulb itself. Finallly, I suggest wrapping the screw part of the camera in heat shrink. They're usually painted metal so don't want a short. Simple heat shrink and some pliers to hold the metal contacts on the bulb holder achieved this.

Then just the process of running the wires through into the cabin etc etc.

- These bulb holders are notorious for trapping moisture and this won't help (although may perhaps provide an escape?). My personal feelings are that while this little DIY might let a little more moisture in, I doubt it's going to make the problem significantly worse because they're already absolutely terrible for it. I'm yet to own an A4 that wasn't afflicted by this issue. I have owned this Cabrio for 6 months and twice had to remove both holders at least once, give the contacts a bit of a clean. This time I have actually rubbed them down with sandpaper so we'll see how long they last now. The obvious long term solution is a soldered wire but not sure what kind of temps these bulbs hit so perhaps not worth it.

- As easy as this part is to achieve (about 2 hours work with all the trim stripping), feeding the cable through to the cabin wasn't easy at all and took an infuriating amount of graft. I ended up going the lazy **** option and fished it through the upper part of the seat, snipped the cable, fed it back through and then resoldered. A method I also used on my previous car.

- The total cost of this DIY was about £7, which was basically the cost of the camera.

- Had this for over a month so far, no issue with the bulb, no issue with the camera.

- I think I would have preferred a better angle on the camera which is facing down towards the bumper and is great for seeing that, but doesn't really improve the overall visibility at the back. It's very useful for parking close to something though