[moklianne]

I've read this 3 times already and don't have a clear picture on what you are trying to do. Maybe I need more coffee.

Are you simply trying to use the wireless on another router and disable the one on the AP with the gateway?

If so, you simply change the IP of the new wireless router to an available IP in your subnet. Routers are usually defaulted to either .1 or .254. Make sure your DHCP options (on whichever router you are using for DHCP) for clients are set to not assign an IP to whatever you pick. If one router wouldn't take the IP, you may want to check this. Some verify if there is a conflict before the setting is applied while others do not. This second router's WAN port would plug into one of the LAN ports on the router that is connected to your internet modem.

Issues with this setup are that you are complicating the network beyond what it needs to be. This is fine, just realize that if you need to adjust a firewall rule, you need to do it twice now. Port routing from outside in needs to be routed from router A to router B to whatever host you want to receive that traffic, etc.