thanks for the help guys. i think i'm going to replace C3 first and see if that helps.
dave, for educational purposes, how do you know that that is the cathode bypass cap? and are cathode bypass caps generally electrolytics? the cap symbol in the schematic doesn't indicate polarity (if its a polarized cap shouldn't there be a + sign on one side?), so i assumed it was a nonpolar cap. is that common for schematics to leave that info out? i was using this site for reference:
http://www.kpsec.freeuk.com/components/capac.htm
i guess next would be the cans (1 is 20, 20, 1 is 10, 15, 15, then there is another 20, 20 in the power supply). how do you guys treat these? do you use separate electrolytics and ditch the cans? I guess you could cut the terminals off the cans and leave them in to retain the original appearance, then find an inconspicuous location for the new caps.
cannikin, keep me posted on progress you make with your gates whenever you tackle it, if you don't mind. I'll do the same.