Were fitted from c1986. You'll have a cylindrical alloy bodied unit on the front chassis cross-member, below the engine mounts, and you'll have two black relays on the bulkhead under the bonnet, close to the battery. The way to disable the system(which can burn the light switch out-If your light switch gets hot, then it's a symptom), is to join two prongs on one of the black relays together, so the system no longer works. There is a diagram and description here, somewhere, that will help you to do that.

ok found the dim dip, so do i just remove it, and then what do i connect in relay thingy?

And I've got a sense of deja vu here but anyway, it's the last paragraph that answers your current question.
http://www.2cvstuff.com/Files/DIM-DIP.pdf

more than likely..!

after reading hole post, now makes sense,
i bridge 1 and 5 with a bit of wire and 2 male crimp terminals..

next thing, easiest way to tell which relay to do this on and what do i do with the other

Once more for the hard of understanding,

You don't need to do anything to the other relay plug, except remove the relay from it.

okaily doakily starting to make sense !

and bridge one and 5

sorry hadnt read that properly, quite tired!

i shall go disable my dim dip tomrow!

and throw it in the trash