Start a Versus mode game against the CPU on the "Hardest" difficulty with the "Edition Select" option enabled. Set the game to one round. Choose any character (Zangief recommended) and make sure the edition is "USFIV". Choose your opponent to be the same character as yourself. Set the CPU's edition to "SFIV", and its handicap to "0%". Then, defeat your opponent to get the "Good Old Times" achievement.