I have an TPLink AC1200 Acess point direct wired to my modem.  It's currently broadcasting 5GHZ wireless signal to a metal building 200 feet away.  Wi-fi works great and have great connectivity if the doors are open.  I have a TP link CP510 that I was planning to mount on the exterior of the metal building, set it up in clinet mode, and run LAN cable inside the building and set up a wireless roter inside the building so I don't have to have the doors to the building open for wi-fi connected devices.  

1st will this arrangement work?

2nd is client mode the approprate way to set up the CP510

I've already set up a Static IP for the CP1200 and base internet connection and attempted to configure the CP510 as a client but not having much luck.

Looking for help and input.

Thanks.