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Body Upgrades

Fitting MGB MkI tail lights


A point of contention has recently been raised on the MGOC BBS as to the safety aspects of fitting these Mk1 lights to a later car.  It must be remembered that MG modified the style in 1970 presumably for some reason, the most likely explanation being that the newer style offered a better diffusion of light.

Whether changing to the earlier style justifies a safety concern is debatable dependent on your use of your car.  At the very least, inform your insurers whom I am sure will not raise the premium, although I have yet to find out.  The simple argument is that many prefer the earlier style so the swap will be done for cosmetic and aesthetic reasons.

As Jonathan Moulds points out below, he found that his gave a sharper light although it could be argued that the same photo shows a better diffusion of light on the original, bulkier later style units.  However, I have also found that over the years, some of the original lens tend to darken.  When Phil had to replace a light unit thanks to careless parking by a flatmate, the new unit was less dark, noticeably so.

If safety is a major concern then fitting halogen or even LED bulbs makes some sense.  Be aware that the LED bulbs need to be the type with an axial ring in addition to the main LED set as the light emitted is in a narrow directional beam, so for side on visibility the axial ring will give a better spread of light.

Also, another point to note is that the US light lens varied in having the brake/side at the top and the indicator below, and some states required that both be red lens.

Another issue when fitting, put new gaskets in and ensure they are sealing correctly to prevent water ingress.

By JC (aka Jonathan Moulds)

How to:

There are two styles of rear lights fitted to MGB's and Midgets. The MK1 lamp was fitted from the cars introduction till the end of the 60's. This item was then replaced by a less curvaceous boxy model. The mk1 style is arguably the prettier of the two styles. I therefore decided that I would like to try to fit early lamps onto a late model car.

The above photo the correct later style lamps.

It is not simply a case of unscrewing the late model lens and screwing on an earlier style lens. (Name a job on these cars that is ever simple!) You need to install the early light base also, as the fixings are different. I managed to pick up some light bases on eBay for £20 and a set of five lenses for £30.

To remove the rear lights undo the two screws top and bottom and salvage the bulbs. There are three nuts on the rear of the light base which need to be removed and a few push fit connectors for the wiring to be disconnected.

The next photo shows the rear lens and bulbs removed. Note: you will need to remove the carpet to get access to the back of the light base. This may or may not be simple depending on how much contact adhesive was used to secure the carpets!

The complete light assembly should then be offered up to the body with both new gaskets and with lens attached. The nuts at the back of the light base can then be nipped up. The reason for this is so that correct alignment of lamp to body can be achieved. It is not possible to align the lamp base successfully without the lens attached. The mk1 style lenses are retained to the light base by a single chromed screw at the bottom of a chromed surround. The top of the surround simply hooks over the top of the light base. This is a much more elegant design in my opinion. The only further mod required is to apply a small blob of silicon sealant from inside the wheel arch pocket to the top of the rear light base. This is because the original base is slightly taller than the mk1 example which leaves a small gap. You don't want water getting into the car after all!

The above photos show both types of lamp installed on my car for comparison. The mk1 style lamp on the left and the later mk2 style on the right. In the second photo I started the car and put a large brick on the brake pedal. It shows that the earlier mk1 lamp is actually much brighter! This is a bonus from a safety point of view as MG lights as a rule, come second place to the small candles you see on birthday cakes in terms of illumination! Do not think I am cheating either. The bulbs were salvaged from the original light base and re-used.

The next few photos show the new drivers' side rear lamp fitted and also illustrate how much better early style lamps blend into the bodywork. The contour of the lens follows that of the rear wings much more successfully.


The lenses and light bases cost £50. However, I should be able to more or less reclaim that by selling off the three spare lenses that I got on eBay plus my original lenses and light bases. I will eventually get new chrome surrounds as there are one or two pit marks. They are cheap enough at around £6.50 each.


Retro appeal...