MAS cleaning

I was reading in another forum, actually having nothing to do with our cars, about taking apart the MAS black box and cleaning the sensor(s) with a q-tip very carefully. It is getting dark, so I think I'll save checking it out till tomorrow, but any of you ever do this? Also how often do you clean your K&Ns? Mine's been in for about 8k now, and doesn't appear all that dirty, but I might just clean it anyway. I still can't track down what is causing my 'loss of power'. I'm wondering if I have a vacuum or boost leak, but at the same time, it seems like I only notice it when accelerating hard from a dead stop or from really low speeds going WOT in the first 3 gears. I don't know if it is my imagination, I drove the car alot this past week at speeds of over 100 in 6th, and I raced that cobra up to 140, and it didn't seem like I was losing power at those speeds/gears. Any other suggestions? The cars got 51k on it...time for a new fuel filter? Also would a slipping clutch make it feel like it wasn't pulling as hard in the lower gears? I don't think my clutch is slipping...I am just getting really paranoid, because it really doesn't feel 100%. Thanks, Geoff