I bought a Mark 1 head maybe 15 years ago. Thinking of selling it. Not using it much, and could use the money. But I'm not sure what the value is what year it is. It sounds great just got it out of service. Local repair man loved it. Can anyone tell me what year it was made. The eq sliders work even though I snapped the actual black rectangular knobs off years ago when it was very cold. Here's some pictures. Flash makes it look terrible. Tolex is in awesome shape. I was doing some research last night and came across this discussion board and figured if anyone knew it would be on here. Thanks in advance.