The truck I got the cruise control harness from had an electrical connector on the Brake Master Cylinder. Looking on Rockauto, they are not showing that particular Master Cylinder. I will need to look into this further. This did come off of an 83-88 truck.
Another issue is the green plug on the back of the fuse box.
Also, there is a vacuum line that comes thru the firewall. The truck I got the harness a previous customer had pulled the brake and clutch assembly from so I don't know what it attaches to.
I am going to look at the Bronco to see exactly where the brain box, (as I call it, as I don't know its correct name.)
If anybody as any links to adding factory cruise to a non-factory truck, please post. I have found links for the 2nd gen trucks and full size trucks, but not these.