Intermittent Rear Wiper

Hi folks,
Many years ago i fitted a new relay to the rear wiper on a Mk1 which changed the rear wiper to intermitent operation, as on Mk2 Golfs onwards. The relay was available as a straight plug-in replacement from VW.
I can't find any references to this on the site, but I'm sure it must still be a popular tweek (saves you having to keep putting the rear wipe on every few minutes when it's pissing down!).
Any of you wonderful people able to send me the reference number of the relay which does this job?…I've tried all the spare ones in my shed, and failed to find the answer!
When I get time, I'll put on the super Mk1 mod I've devised to keep the drivers hands warm on these cold mornings, involving simple re-ducting of the warm air outlet!
cheers
Oldfart

Can't believe nobody seems to do this mod anymore…or are you being shy?
- Intermittent rear wiper is soooo much less hassle on a car which constantly mists its rear window with spray on a wet road!

I've got one in mine, but it works so well I haven't looked at it since I put it in so I can't remember which one it is. I'll have a look tomorrow.

brill, thanks!