Replacing Rear Lights

Damage caused in France

the other one was filling with mud and leaves

In order to replace the light clusters, the whole rear bumper assembly needs to come off first.

Start by removing the internal covers which give access to the bulb holders. This will reveal two mounting bolts which screw into the bumper itself.

Do not undo the bolts yet, but do remove all the bulb holders from the light clusters - they should only require a quarter turn to undo.

Removing the number plate will expose the other two setscrews which go through the body and bumper.

Access to the heads of these setscrews is found by lifting the carpet under the boot lamp assembly.

Before undoing any of the setscrews, remove the spare wheel and drill out the rivets which run along the edge of the bumper under the body

This is why the spare wheel needs to come out BEFORE you start drilling rivets

(Yes, some of the drilling created new holes in the spare wheel well).

With the rivets removed, carefully undo the 4 setscrews/bolts which hold the bumper on and ease it back off the supporting brackets. During this process, the wiring for the numberplate lamps will be exposed. The 4 connectors should just pull off the lamp assemblies.

All being well, the rear of the car should look something like this

With the bumper off, the 6 mounting bolts for each light cluster should be obvious and can be undone. On mine, a couple of them were seized and had to be cut off because the bolt was turning in the "captive" mount cast into the plastic. Access to one was difficult from the rear so I had to break the lamp assembly and cut from the other side. Fortunately, they're fairly soft metal and cut easily with decent junior hacksaw.

These are the replacement clusters:

Note that these are from a 1979 vintage SD1 which had seperate side and brake lights. The side light void is present on all SD1 clusters, but not used on the Excel. On your old units, there will be two plugs which can be transferred to replace the two small bulbs visible in the centre of these units.

At this stage it is worth carrying out a thorough inspection of the bulb holders and choosing which ones you are going to replace (N.B. the brake lamp holders are no use unless they are combined side & brake light like those already fitted).

The SD1 lamp assemblies have drain holes in the lower edges

BUT these will be on the TOP edge when the units are fitted to the Excel and should probably be sealed to prevent water or anything else getting in.

Conventional wisdom says that you should now carefully cut away some of the foam on the opposite edge to the drain holes and drill some new drain holes before proceeding any further.  Having disassembled a lighting unit, it's unlikely that water would be able to drain through any new holes. Use your own judgment.

For the obsessive detailers amongst us, NOW is your opportunity to clean all those bits that will never be seen until you do this job again.

The lamp assemblies should go back into place quite easily, attaching via the 6 captive bolts.

The bumper can then be test fitted to make sure that everything (including new bulb holders) is working

Remember to reconnect the number plate lamp wiring too

Finally, the 4 setscrews can be fitted from inside the boot and a row of new rivets popped into place

Don't forget to put your number plate back