So I just picked up an near mint Super Festival amp and after playing with it for a few days I have some questions. First, there is a jack on the right side without any designation. I assumed it was for a footswitch to turn on/off the overdrive? I looked through the manual and it isn't listed. I went to the Peavey site as well and no luck. I even tried my footswitch from another Peavey amp that I have and still nothing. What does this input jack do and what footswitch do i need? Secondly, does anyone know how to read Peavey serial numbers? I believe it's a 1974, but would like to confirm. Thanks very much!

