[Electronic M]

Convergence pots are wire wound types. Some contact cleaner won't hurt. I haven't seen this in the pots Zenith used, but on the convergence pots RCA and the rest of the industry favored sometimes either the form the wire if wrapped on burns up or the wire gets loose and starts getting hooked on the wiper and sometimes that destroys the pot. Take care while adjusting.

Also only use all plastic construction alignment tools on the slugs in the inductors on the board. Metal hex tools will not only crack the slugs, but also the metal changes the tuning of the slug while near the inductor so after dialing in an adjuster merely removing the adjustment tool will throw it off if the tool is metal.

BTW, it's generally frowned upon to create multiple topics for the same TV. You've been creating a lot of topics to ask about various aspects of your Avanti that could all be done in one place.