Congrats, long struggle, but good outcome & experience to share with others attempting this journey. If the tuner is working fine, I'd leave it. It is a bit of a PITA to take apart with the dial string. Certainly does not hurt to clean the front panel switches,also the de-emphasis switch in the back. With age the tuners can get scratchy noise as you tune them, so you eventually will have to clean the var cap contacts when that happens. In the mean time enjoy.