i dont even do a sweep. i start at 5 hz higher than tuning, and play one for a couple seconds, then move up. about 10 o more times, then he'll tell me where i peak. may not be the best...but if i tune at 35 hz, i dont see myself peaking under 40 in my car.
also, i'll bring my scope and meters and tools tomorrow to set your gains. if we get there early enough we can tweak some shits on your shits. i wouldnt turn it up to the point of clipping, but get it to where it should be.
49 hz sounds realistic. i think explorers are in the high 40's to low 50's range. at least a guy at a shop told me that they like the 50's one time
i think any commercially available cd is considered music. tho...i think one or more of bass mechaniks cd's are not allowed, but dont quote me on that.
and x2 on asking questions. dont go first, see how things play out. ask a few people questions on how to do it. i'm sure greg will give you a quick rundown on things.