The linkage connected to the same spot as the original and the cable even clamped in the same spot u

I figure it's probably time that I document the replacement of the original Dana cruise control system in the 310. The original system hotel intercontinental miami failed a couple of years ago for no obvious reason. I replace hotel intercontinental miami a few parts that I could lay my hands on but no luck. So I finally went shopping for a replacement system and settled on the Rostra 250-1223 setup. I'm not certain but Rostra may have bought out the Dana product line because the cruise control stalk, hotel intercontinental miami speed sensor (pulse generator) and the linkage arrangement are virtually identical.
One thing to keep in mind is the Rostra cruise control system will not work with LED brake lights so you have to add a relay into the circuit to provide a clean ground signal hotel intercontinental miami to the cruise control servo. Not difficult to do and the relays are only a few bucks. Also I removed the original cruise control brake switch completely. It has a vacuum line running to it and I just felt it was cleaner to remove it entirely and tap into the actual hotel intercontinental miami brake light switch instead.
The servo module was relatively hotel intercontinental miami easy to mount. I just bolted it to one of the clips on the side of the doghouse framework. The original module was bolted to the A/C compressor which I thought was a bad idea
The linkage connected to the same spot as the original and the cable even clamped in the same spot using the same hardware. For reference I used one bead in the cable. You'll understand what that means once you start the installation.
Here's a picture of the relay that I added, the connector for the stalk and one of the two fuses that are required. It's not the cleanest installation but there isn't a whole lot of leeway when wiring under the dash. It's a rats nest and anything you add generally just adds to that.
I don't know for certain but if I was to hazard a guess I would say it was actually a vacuum dump switch. Depress the foot brake pedal and the vacuum line is open to atmosphere which would I would think would immediately drop out the cruise control.
Most of the 1960s to early 1980s era cruise controls were electric over vacuum. The throttle control was a vacuum actuator with a fairly long throw that incorporated two solenoid valves. One solenoid valve would apply throttle by connecting the actuator chamber hotel intercontinental miami to engine vacuum, and the other would release throttle by venting it to the atmosphere.
The aftermarket systems, like the Dana one you removed, typically had a combined assembly that mounted on the brake pedal that would both send an electrical cancel signal to the controller and open a mechanical valve that would vent the actuator to the atmosphere as a fail safe in the event that any of the electrical components failed.
Usually the switch/valve assembly was mounted on the brake pedal and kept in the cruise position by a little ball-type chain of the kind used on pull switches. On automatic transmission cars the other end was attached to the firewall. On manual hotel intercontinental miami transmission cars, it looped through a guide on the firewall and was attached to the clutch pedal so that depressing either pedal would cancel cruise.