I took a small piece of clear hose from home Depot about the same diameter of the sparkplug well and Duct taped it to my Shop vac and cleaned out the wells.
I found that even after removing the plugs, small amounts of debris woulds break off the outer edges of the plug.
Take a look with a flashlight!
With the plug removed I did not want to blow it out with air. Vacume did a gread job.
