EDIT:
I talked to the guy at:
http://www.thecruisecontrolstore.com/ford/ Who used to sell the kit to fit my 99 E350 PSD.
He told me Ford no longer sells the steering wheel for the van. And since they don't he can't sell the kit. But what he did tell me is, that I don't even need the brake pressure switch pictured below. See the 2 pin connector for it? Under the coolant tank is a two wire plug that's plugged into a gray dead end plug. Snip the plug off, and tie these two wires together to complete the circuit.
The brake pedal is already wired with the switch for the cruise control. All you need to do is install the 99-00 E350 steering wheel
(it has to be a 99-00 steering wheel or it won't work), and correct clock spring.
Just so happens I have a great salvage yard by the house. So next week, I'll go digging for one. And I am ordering a clockspring from a f-250 today from Rockauto.com.