I would not alter the boom in any way what so ever unless it is done under the direction of a structural engineer. Doing so, your boom will loose any certification it may have. Any failure of the boom after it was altered by you, will be on you. You might save a few bucks up front but if someone is hurt or killed because the boom failed, how much did you really save? I would not want that kind of liability. But to each their own. It's your money.
