While at the local hobby shop I found one of these empty glue bottles for $2.00. Came home filled it with water, keeping it upright, squeezed the bottle. The very small opening in the tip produced a forceful spray of water and considerable grounds dripped out of the group head from around the gasket.
As a matter of routine now, following the puck disposal, I take a damp cloth (careful the grouphead is hot) wipe the group head and screen, take my bottle filled with water and move around the gasket. Only takes seconds and no more leaks.
Below is an image of the bottle that I use for gasket cleaning.





