Several years ago, I pull my tack amp and revived it using the "cigarette butt trick" and it work for several weeks and then quit. Now, I am going to scrape away silicon and reshape female socket holes to make better contact and check sensor adjustment. Mine is dirty and appears to be further away than the 2mm clearance I read about somewhere on this site. Does anyone have a good procedure for removing, cleaning and adjusting the sensor? Thanks!