I'm running an Audiovox CCS-100 cruise control in my 54 truck with a 235 engine. The Universal Cruise Control kits sell for under $100.00, and if you've got some basic skills is not difficult to install. They are commonly used on motorcycles because of their compact/simple design.
Being a universal kit you get plenty of optional stuff to mount the servo to the throttle linkage. My setup is a little different than the stock single carb so I had to do some extra tweaking but the system works like a champ. I'd suggest you "Google" Audiovox CCS-100 as there is plenty of info available. Incidently, if you're running a stock engine you won't have to go through all the vacuum reservoir fabrication that is shown when adapting it to a motorcycle.
Dave
