OK, it has come to my atention that I don't have a good guitar for metal. I have decided to but an EMG 81 in a partsacaster I built last year. Since I have never used active before and I have seen that you can buy an 81 on ebay for about 50 USD if you just buy the pickup, no other stuff, I was wondering. Would I need anything besides a 25k pot, wire, a stereo jack, a 9V clip, and This?