Probably going to find a bunch of crap in the carbs, maybe even some gummy substance. Sounds like you will be able to get away with out separating the carbs to pull the mixture screws. There are 3 or 4 different kits out there for the cdkII carbs. The real cheap ones will have a mesh material for the fuel pump and pulse diaphragms. That material will work ok on the liquid side, but will NOT work for the pulse side. It will not pull a vacuum. The two mid range kits will have a solid material like the oem for the pulse side, and then you have genuine Kiehin at the top of the range, and you pay good money for those. A cheap kit is about 25, mid range will be 30-50, and Kiehin is 50+. This is per carb.
You will need to pull the carbs all the way down, and pull and clean the intake screens. Be careful and don't bend the needle arms. I would also get a pressure checker and test the pop off, and make sure the regulator diaphragm goes back in the same way it came out.