I don't want to assume where to connect the X-Surf-500 but it appears it connects to the bottom of the ACA500 (Not the Plus) which has the Ethernet Port pointing to the front just under the Left CF Card. There is no other way to connect the X-Surf-500 but I just want to clarify this before connecting it. The ACA500 Plus has its connection port on the the top but the original ACA500 its on the bottom although the silkscreen label is on the top. I know its an older card but its the card I have to play with right now. If I am correct in my assumption please let me know and if not please explain how to properly connect the card.
Far better to ask a stupid question than to make an improper connection resulting in damaging the cards.