I had to get a new login, could not get the old one to work. Now besides a 2011 CV I just got a '83 Box. I found myself driving it quite a bit in the rain lately and it absolutely is a pain not to have intermittent (Interval acc. to Fords Brochure) wipers. Especially because the slow setting is a little fast imo. So what are my options of adding this? There are aftermarket modules for Mustangs but they do not work with our Wipers that have a hidden Park position. I can buy the intermittent Stalk/Switch but when I look at the connectors of the interval Governor module (not cheap) it looks like it is not going to work. So I think that the Vehicle harness might be different for this option. Not to mention that Ford/Mercury is using a different Governor than Lincoln. Anyway did anyone here added this feature to his Car?

I can't say I've seen any base non-interval cars swapped to interval wipers, at least thus far.

AFAIK, as you've found, there's a magical little black box that controls the interval function, and I'm sure the connector to the wiper stalk is way different to also allow for the input of the time delay.

I'm not sure how crazy you'd have to be to grab all the associated wiring and control stalk from a donor car if you have any salvage yards in your area. Unfortunately I don't have my wiring diagrams handy at the moment, otherwise I'd look at it to determine how wildly different the configurations are.

Basically if the connectors of the Interval Governor module are the same (one male one female). I think that the connector for the switch is the same according to the wiring diagram so there would be a chance of it working. Body Harness would have to be the same. Interval switch and governor are not cheap but at least they are available.

I got it to work
Here are the parts I used;
E5AF-17C476-AA Windshield Wiper Governor Control Module
E1AB-17A553-CA Windshield Wiper Switch W/intermittent

There are a lot of Governors with the 17C476 part number but not all will work for the CV or GM. Key thing to look for is if the Governor will work with the Park position of the wipers.
Best not to do this when it is cold due to the many plastic clips you need to unlock. Getting the steering wheel covers off takes some bending of the covers. In the cold these snap a lot earlier than if it's a bit warmer