You spent hours carefully printing and building Greg's Hinged Accessible Extruder http://www.thingiverse.com/thing:8252 only to realize that it has filament slippage issues. You don't want print one of the redesigned parts. That would take hours! Instead, print one of these in minutes and snap it on!It'll wiggle a little, but it'll work just fine. For a tighter fit, put a little piece of wet paper towel over the holes, then press the filament guide into place.