I've heard Tony Stark is in the crowd tonight! You know what that means to me? I got this nickname 'cause I identify so much with his armor-wearin' wonder of a body-guard! Shellhead never quit on a fight, Phil... And neither will I!
Born in the lower-income north area of Bay City, Eddie March was a successful boxer. As his career wore down he became a sparring partner and friend to Happy Hogan. A serious blood clot forced Eddie to retire. With medical expenses mounting, the money he had saved from boxing was quickly running out. He wasn't sure if he was going to die or go broke first.
Happy Hogan was able to get him a job with Stark Industries, and Eddie eventually became trusted enough to where Stark revealed he was Iron Man. However, the strain on his heart was causing Tony to consider finding someone to replace him, and Eddie volunteered. Eddie felt that if he was going to die, he might as well be a hero. He trained with Stark for weeks, and a hotline was set up so Tony could call him whenever he was needed.
Eddie fought Crimson Dynamo as Iron Man, but was severely wounded. Stark paid for his medical expenses, and gave him a spare set of armor as thanks.
While Iron Man was battling the evil Doctor Spectrum, Eddie donned his spare armor to help. However, Iron Man had left to make a repair and Eddie was overtaken by Obatu. Thor arrived to help. Obatu had taken over Eddie and his armored body. Thor was surprised to be attacked by what appeared to be his fellow Avenger and friend Iron Man. In the battle that ensued, Thor damaged Eddie's body even further. Iron Man returned in time to reveal the ruse, smash Doctor Spectrum's Power Prism, and free Eddie's armor.
Stark attempted to save Eddie from his grave injuries. As a result, like Happy Hogan, Eddie was also briefly turned into the Freak, an unintentional side-effect of Stark's 'Enervation Intensifier Ray', intended to accelerate healing and vitality.
Restored to normal, Eddie asked Stark for help in finding his brother Marty in Vietnam. Marty had been injured and later mysteriously disappeared. Marty was found in a hidden city. After Iron Man ensured Marty March was safe in Southeast Asia, Marty made a decision to stay in Vietnam. 
Years later, Eddie was one of a number of others with experience in using the Iron Man armors asked by James Rhodes to help battle Ultimo. Once again, he was injured although he put up a valiant effort.