variable timing for intermittent wipers, 124

[tld]

I am wondering if anyone has changed their single intermittent wiper timing to variable timing? Thinking along the lines of patching into the intermittent circuit ahead of the set timing sequence and utiliziing the front/rear speaker fadder on the console to operate a variable time windshield wiper control. Is this feasable or even worth the effort? I would really like to have more control over the monowiper. Any and all comments will be greatly appreciated.

[Fourings]

Back in the mid 90's VW had a wiper relay that would allow a person to adjust the intermittant from 2 to 22 seconds if I remember right. All this without changing any hardware. When the wiper switch was turned off from the int. position the wipers would cycle once and the timer would start. When you switched to int again it would set the time interval, provided it was less than 22 seconds. Starts raining more or less, change the time interval. Brilliant design as it doesn't need any additional hardware, and it's easy to get the time interval right the first time. I've got one in my Audi and it works great. Plugged right in w/o modification. Only problem is that most folks probably didn't even know it existed and it probably didn't know how to use it. I don't know for sure if that relay is still available, or how easy it would be to get it to work with a W124. VW part # is 357 955 531.
If you use that relay and get it to work I'd be curious how. This was probably used on Jetta's in the mid 90's.
Good luck.