1 JBGretschGuy 3 months ago The blacktop filters are attached to the base plate with solder and four tiny screws. If you unsolder them, or cut through with a Dremel wheel, you can separate the brass base plate. You then enlarge the 12 holes for the poles to poke through, and drill two tiny holes for the Filtertron mounting screws. Also, you may have to enlarge the opening and re-radius the corners of the mounting rings. Once assembled, it looks like this.