Flickering main beam and brake lights?

[Q Plate]

Has anyone had the same snag? Guessing its an earthing problem, checked the brake lamp switch contacts and they seem fine, been told they just flicker now and again whilst driving. The main beam does a similar thing whilst driving with normal headlights on, they will just intermittently come on and then off. All lights function correctly when tested stationary.
Anyone tell me where the earthing points are?
Thanks.

[GJR]

Hi Q Plate,

Probably not the best person to answer this question but it does sound like an earth fault. According to Steve Heath's book (which is definately worth getting if you haven't already) there are a few earthing bolts on the chassis around the engine bay and on the transmission tunnel, underneath the console in the cabin. From the book it looks like the front lights are earthed near the steering rack ? There might also be some images on The Griffith Pages, but the site doesn't seem to be working at the moment.

[Q Plate]

Thanks mate, that will give me a starting point, must get myself a Steve Heath Bible.