I have a KW Matchbox with the directional coupler and SWR meter. The meter's calibration pot is intermittent. I'd like to replace it. Is it feasible to open the can that's mounted to the unit's cover and which evidently houses the meter, pot and CALIB/SWR switch? And get it closed again? :) How? Any tricks I need to know? Any advice as to what kind of pot (taper) to use? Thanks everyone! Steve K8JQ