Choke and idle problems

Ok, I need a little help as to where I should start. First off, I've been riding the bike for a couple of months unaware of the fact that it had no air filter. I'm currently trying to locate some filter foam or something to put on the steel mesh inside the airbox. It's an '82 KZ440 G1. Lately, it's been difficult to start, it runs like crap with the choke on (right cyl misses, hisses, and pops like mad) and the bike won't idle until I've been riding for 20 minutes. Something else I want to add is that I recently discovered a pinhole fuel leak under the paint on the tank, so I have reason to suspect there may be rust particles doing their worst inside the right carb (or both?)

I know I have to pull the carbs to clean them out, but before I put them back on I'm going to get a proper air filter and a small inline fuel filter.

Where should I begin with the carbs and how should I go about cleaning them/checking them? Last time I did this with my 1000, I didn't have the best of luck.

Well first off plan on addressing the tank first. A pin hole could be just enough for an engine fire under the right conditions. Secondly if it is that rusted then the carbs are suffering for sure (that and the lack of an air filter).

The carbs you have have vacuum diaphragms,IMHO, this is probably going to be bad on at least one carb. Be very careful in taking these apart as you don't want to damage the diaphragm. I'd drain the bowls into a cup and see what came out first. Next I'd pop the tops off and inspect the diaphragms. Depending on how bad these are is going to determine your best course of action. Might be a quick clean and re-sync. or it could be some major dollars.