I need to replace the Light Bulb in my Speedo and while I know how to take the Instrument Binnacle out, please could someone tell me Specifically which Screws I need to undo in order that I can then replace this Bulb, although I would be replacing them all with Brighter Bulbs

 

Alex
The binnacle comes out, on the back of it are four or five black push-in bulb holders. You carefully pull them these out with your fingers (they just push into the blue electrical flexible circuit board and NOT ruining the copper contacts is essential) and the bulb is a push-fit into the black holders. I did mine before the age of LEDs and used 5 watt push fits, which are excellent.
Now if you look down the hole the black holder goes into, you will see there is a green bulb shield. These go black and opaque. If yours are (and test by using a bulb in the dark once the binnacle is out) then it is more complex:
In this case the white part of the binnacle has to be separated from the black surround. About 8 tiny self tappers have to be undone and the white part comes off the black part. Now the opaque bulb covers can be removed and this also transforms the lighting. I recommend this in any event.
Make sure you take it apart on a large table covered with a white sheet or tablecloth.
Pics of what I am talking about:

 

Hi Greg

Cheers!

That was mega useful information but before I start to take it all to pieces, I was playing around with the Rheostat and at some point all the lights got brighter and so I am wondering if that might be the problem

As I think it might be a good idea to do away with the Rheostat altogether as I've never had the Dash lights so bright, that I've ever felt the need to turn them down, so how would I go about removing the Rheostat or even taking the Wires off

Does it just consist of 2 wires that need to be joined together or is it a lot more complicated than that?

 

Just disconnect and join the 2 wires at the rheostat. Leave the rheostat in place.

 

Hi Sanchez

How would I go about disconnecting the wires if I don't take out the Rheostat so I can see to undo them

How are the wires fixed to the Rheostat or should I just cut the wires with some cutters?

 

When I did mine on the 88 XJS H&E the wires were plugged into the rheostat (2 female connectors) The same method was used on my 85 XJ6. However, I have heard of episodes where the wires were soldered to the Rheostat and in this case there were bullet connectors were further down the line.

 

The wires just pull off, you need to drop the shin level trim to get at them. But if, turning the stat right up they are bright enough, why bother?

 

That's a very good point you made there Greg but I thought if the Stat was flaky, then it might be causing some sort of a voltage drop to the bulbs

 

It does get a little brighter if the wires are connected together rather than leaving them connected to the rheostat.