Thanks for confirming.
Will do the move to Single NIC.

In case you need help with this, here's how to migrate from 2 NICs to 1 (instructions are from MS Tech Support):

To change the SBS server from 2-NIC mode to 1-NIC mode, it is actually not complex if you keep the LAN NIC and remove the WAN NIC. The main procedure may involve following aspects

1. Uninstall ISA from add/remove programs
2. Disable the WAN NIC and remove it physically
3. Run CEICW wizard again to re-configure the SBS server in one NIC mode.

However, if you want to keep the original WAN NIC, this is actually a process of Change LAN NIC and more steps should be involved. So, first we still need to remove WAN NIC and configure the SBS server on LAN NIC only. Then, make sure everything of the server is running fine when server is in 1-NIC mode of internal NIC. The difference is, you may not need to remove the WAN NIC physically, just disable it in the device manager. After that, consider the following procedure to change the NIC from LAN to WAN.

4. Enable the original WAN NIC and disable the LAN NIC
5. Manually set the IP address of the WAN NIC as the same of the original LAN NIC
6. Run the SBS integrated setup. You do not need to change anything, jut set the Server Tools to Maintenance and finish the wizard
7. In the Server Management Console, please run the “Change Server IP address” wizard from the Internet and Email node. Please set the same IP address and subnet mask to run the wizard.
8. Finally, run CEICW wizard again. Please do not select “keep the original configuration”. Please just go through all settings and make sure they are correct. Keep the original settings in wizard if they are already in correct value. Finish the wizard and make sure everything is fine.

Will keep the LAN NIC (its easier and Gigabit).
Thanks for the advice cocospm