that might be alot of work for nothing. I would try to pinpoint where your problem could be before doing any work.Make sure the pump isn't running,shut the main valve off, put your ear to that line going out to the well,and listen to see if you hear any water going back.This assuming that you don't have acheck valve at the tank. Do the same thing to your holding tank. If you hear water going back to the well then i would go outside to see if there is any water in the yard or out by the well casing. If nothing in the yard or well,i would take the well cap off and listen for water spraying. If you have a well seal i would put your ear to the line that goes into the seal and listen for water there. A well seal is a round fitting that sits in the casing with the drop pipe for the pump going right down the center of it.