That gooey stuff might be the sillicone anode cap deteriorating.
I've found that HV problems are generally due to dirt, and some sets, no matter how muych you clean them, never really stop arcing anyway. But - wipe down the whole HV section, clean the lead, clean the suction cup, and clean the glass around where it plugs into the tube. Clean clean clean. Then clean again. Arcing along the CRT itself is bad mojo, and arcing through the neck is really bad (old zenith color sets from the 70's did this trick, IIRC). Make sure your ground return is good and solid, and contacting the 'dag coating well. It shouldn't be too hard to make it stop.
Hey, how about a few inside shots of the TV set?
