If you're going to use a volume control, you will need to use a 9/32-inch bit to make a hole for the volume post. The next thing I'd do while the soldering iron is heating up is take some steel wool or sand paper and lightly sand the back of the volume control. There's a fine. oily finish on the back of these to keep them from rusting, but it needs removed before you start to solder. Read on!