So I have tons of experience working on bikes, and by now know a lot about compatibility of various parts, but there are some sort-of newer parts that I've never actually worked on. Such as integrated crank/bb systems, threadless steerer systems, and Shimano STI levers. (My bikes have all had downtube shifters or barcons, because I like the philosophy a bit better and for durability, which was more of an issue when I built up my last nice bike in 1995. I have worked on bikes with Campy Ergo levers.)
I'm currently working on a friend's bike, a Cannondale from the early 90's that has 8-speed Ultegra STI levers. I'm giving him a Technomic stem, so I have to remove the levers from the handlebar, and can't figure out how to do it. I've not searched around too hard, but it doesn't work like standard (old-school) brake levers, aero or not.

I'd like to hear how you remove STI levers from the handlebars, as well as how you install shifting cables. Brake cables are easy to spot.
here's Shimano's technical diagram of the current 10-speed Dura Ace levers, if it helps for reference in explaining things. Thanks.