Mark, I have a '92 12v which was an import and had no CC. I looked at all the options and eventually went to Conrad Anderson to have one fitted. Fantastic service, and its been a real godsend. Besides a wire issue being rattled off a connector its been trouble free and maintenance free.
I went for a CG5 control and CG55 actuator. I have a manual and it just works, having now covered about 50,000+km with it fitted over some very bad roads.
Here's a snippet from my blog..
It was whist driving in Zambia that the cruise control started to malfunction. I bought an 80 series as I wanted a car as free from electronics as I could get, however as you all know driving one of these trucks without cruise, for hours at a time is not fun. So after the Morocco adventure, I took the truck to Conrad Anderson in Birmingham to have an aftermarket system fitted. It had worked perfectly up to then, but after the pounding the truck took over the last 4,000km it had obviously had enough. With the prospect of another 4,000km to go, I decided to call CA and see if they could diagnose the problem. I called them on the sat phone and explained that I was in Zambia and the cruise they fitted was playing up. The chaps remembered the vehicle and talked me through a diagnostics test over the phone, whilst they listened to the beeps the system was emitting. After 20 min, lots of beeps (an expensive Sat call too), they gave me some instruction and presto it was sorted. Never gave me more trouble! They even called me the next day to see if I was all OK. Hats off to Conrad Anderson, sterling service for an item that was well outside warranty!
I'd highly recommend Conrad Anderson, they're based in Birmngham.