Wiper control box 88-

I'm trying to compare the small box that screws to the lower trim under the steering wheel.

It has a large blue 8 pin plug attached to it & I believe it controls the intermittent wipers.

My box has only 6 pins, but 8 wires, and I think that the extra 2 wires are for the variable control.

Does the box in the XT version which had variable speed wipers have the extra 2 pins?

I'm looking at the possibilty of a retrofit with a potentiometer to make it work.