@ Condor - Holy crap! You gelded a Kaywoodie?
Regarding the stems, You didn't mention the brands. Some stingers are removable, if yours are not then inserting an alcohol soaked pipe cleaner, and letting that sit in the airway for an hour before beginning to scrub, will do a lot to soften up the residue. I repeat scrubbing with as many pipe cleaners as needed until the airway, including the opening in the stinger, is completely clear. It also helps to insert the soaked pipe cleaner into the stem via the opening in the stinger if it isn't completely plugged. A paper clip is an excellent way to open up a plugged stinger.