Number Plate Light Holder.JPG
As you can see from the picture above these are the units that hold the bulbs; Note that both in my GT were mounted with the spring (see the right of the unit nearest to you in the picture) to the right and the hinge to the left (see the right of the rear unit in the picture) as you look at the back of the car.
HEALTH & SAFETY:
Before working on any electrical systems, you should disconnect the battery (I didnít, but thatís what I advise).
REMOVING THE UNIT FROM THE BUMPER:
Another user on here did say that you should be able to slide the unit against the spring and the hinge side will drop out, so try that first; on mine the right one did slide a few mm, but it wouldnít drop out, the left one didnít slide at all.
If that doesnít work, itís a bit of a pain and I recommend having a couple of iPod dismantling tools (I did break a couple whilst doing it) and a very thin long screwdriver.
On the spring side there should be a flat notch to lever down from, use the Ipod removal tools to lever down from there to the corner nearest to you so that you can get the thin long screwdriver in through the gap.
Angle the screwdriver so that goes over the spring and push the spring in, then pull that side out, with the other side then freeing itself from the hinge type hooks on the other side.
Twist the electrical connector half a turn and that will release the bulb from the unit, and the bulb itself simply pulls out from the connector.
The picture above isnít mine, I took it from eBay which is advertised being from a 147, but it does appear to be exactly the same as that on my GT (JTD 55 Plate).
As for bulbs, I did order LEDís of eBay:
I wouldnít recommend buying these, they are a very tight fit, and one only worked for a second before going out, then when I went to pull it out, the top end came off, leaving the back connector stuck in the socket
I then went to Halfords whom do have 501 LEDís for £10, these didnít work at all, so I just bought the regular 501 bulbs.
Ps; thanks to all the other users that have posted bits and bobs in other threads which helped me do this guide.