A cutting guide for trimming the center conductor of a stinger. The cutting guide may include a housing that is adapted to receive the stinger conductor and provide a reference plane for trimming the conductor to a desired length. The housing may include a receiving end for receiving a predetermined portion of the stinger and an exit end through which an excess portion of the conductor protrudes beyond the desired cutting plane. The housing may include a socket having a receiving space for receiving the threads of the conductor and a barrel having a bore through which the stinger extends. Alternative embodiments include a length-adjustable housing and a housing with multiple bore lengths.