Too much to read in my previous Post?:shocked:
I am not going to discuss the nature of your unorthodox setting, just taking it as is
You already Hardware! OK Just use the Max. security that it can provide.
1. Unique SSID
2. MAC Filtering
3. No extra IPs available from DHCP.
4. WPA2 the best. No WPA2, use WPA, No WPA, use WEP.
You feel that this is Not enough?
Use NetBEUI for File sharing and unbind TCP/IP from it.
Install
AirSnare. to detect intruders (a little complicate commotion, but hey it adds security

).
:sun: