Hi,
Have some issues with KC-2600 throttle setup, think it might be the actuator following this diagram:
Foretravel Motorhome King Control: KC 2600 Throttle System Diagnostic Chart... (http://www.allthingsforetravel.com/2020/03/02/king-control-kc-2600-throttle-system-diagnostic-chart/)
Anyone know the vendor of it? Bosch? Is there replacement part?
To my knowledge parts are no longer available.
A much better flow and diagnostic is here, your linked site is just a poor copy of these details.
Semi Truck, Bus, RV, Service Vehicle Cruise Control Installation (https://www.cruisecontrolking.com)
You may find some parts at various wreck / junk yards. The other thing some (Country Coach, Foretravel, Monaco) have done is convert over to a Pneumatic setup (Pedal, TPS sensor and air actuator) I've been told its about $1500 in parts but then a quite a bit more to have a shop install that. I you are handy you can do it yourself.