From this high res image I found on the internet. It looks like the Tracks for RX2 and TX2 are nice and obvious on the top of the board.
![k8400_mainboard.jpg]( "k8400_mainboard.jpg")
Perhaps cut those two tracks and reconnect them to other general IO pins and update your firmware pins to suit.
Then you can use this serial port once you wire the pins to something useful.
Perhaps cut those two tracks and reconnect them to other general IO pins and update your firmware pins to suit.
Then you can use this serial port once you wire the pins to something useful.