If you can get a pair of pliers around the back end of the pin, then you can twist the back end off. The pin usually breaks off at the little neck. Not a problem if you don't mind the pin. But, if you do, then you have to separate it some how.
Personally, I don't think they had the service sector in mind when they installed the Pin.
On later releases, Capcom ditched the press pin for a security bolt on one side and a nut, sealed by a clear Capcom security sticker, on the other. Seems Capcom got the memo.