Sentence:  Hotrodding Marshall's became a large cottage industry and a few of the guys who started out with great Marshall mods went on to form their own successful companies, Mike Soldano, Bogner, Paul Rivera (who was an early <WSD>mod man</WSD>, initially making his name modding Fenders.) 
Meaning of the word marked with <WSD> tags:  A person who experiments with and modifies the internals of machinery, electronics(,) or software that has been mass-produced; a creative mechanic or technician.