I'm going to replace the original Mallory cap can on my '78, and I have a question before I order a new one. There's a 22uF soldered from one of the leads of the can to ground. Is this wired in parallel in order to change the 1st filter cap to 42uF? Or is this added capacitor there to replace the original 20uF? I love how the amp sounds, so I want to keep the values the same as they are now.