a weld gun for performing a welding operation on a workpiece includes a pair of opposing arms , at least one arm movable relative to the opposing arm to apply pressure to the workpiece during a welding operation . a pair of identical or mirror image side plates support components of the weld gun to establish critical dimensions of the components relative to one another , while preventing tolerance buildup of critical dimensions at critical points . a guide block is connected to one of the opposing arms . the guide block has a non - circular aperture formed therein . an electrode adapter has a non - cylindrical rod portion slidably received in the non - circular aperture formed in the guide block for preventing rotation of the electrode adapter . a hose fitting is attachable directly to a rear end of the electrode adapter for communicating with an inlet water port and an outlet water port formed in the electrode adapter for providing a routing of coolant directly through the electrode adapter only .