Popping LED's in amachine is a snap. Just check the anode and cathode of the one already in the machine, desolder it, and solder in the new one. My Dreamcast has been sporting a blue light and clear shell since 2000
My saturn ont he other hand unfortunatly had the pad come out with the LED so I had to scrap some green off the board and solder over a little 33 gauge wire to complete the connection. But now it has that pretty blue glow too
Shaneus: If you were putting a 3.8V LED in a socket only providing 3.3V, then it just wouldn't glow at it's optimum brightness. You could always tack on a CR20XX battery and a resistor to drop it down and give some extra juice needed. But dropping juice like that would heat it up. Just try to pick a close LED. Blue's are 3.5 and Red/Green is 3.2/3.3.