That thread has very little on how to retrofit cruise to a non-e-gas model. I've been looking for a way to do this for a while, and this is the best option I've seen so far.
CCS100 Cruise Control
It's an aftermarket generic cruise control kit. A buddy of mine has installed them on a couple of cars and several motorcycles and says they work really well.
I'm likely going to order one this spring. If I do then I'll take a lot of pics and do a write-up for the forum.