You want the cord to be long enough. A common 6 footer won't get you far especially if quite abit of the length is used inside the cabinet. Shoot for at 12 ft or longer. And the wire size should be 18AWG for power cord replacement - same as the originals which are rated up to 10 amps (games are typically fused at 8 and under). 14AWG is way too big.
I used 16AWG to replace one of my power cords. Even 16AWG is too big - I had to resort to making the exit hole larger.
Ed