How do I create a Custom RP2040 Board for port/RP2/ ?

[pi-plates]

I have a custom board with 2X the flash memory of the PICO. To address this, I thought it would be a simple matter of creating a new board called PICO2 in the PORT/RP2/BOARDs directory and follow the build steps in the documentation. But every time I run make BOARD=PICO2, I get the error:

**```
PICO target board is pico2.
CMake Error at /home/pi/pico/micropython/lib/pico-sdk/src/boards/generic_board.cmake:22 (message):
Unable to find definition of board 'pico2' (specified by PICO_BOARD):

 Looked for pico2.h in /home/pi/pico/micropython/lib/pico-sdk/src/boards/include/boards (additional paths specified by PICO_BOARD_HEADER_DIRS)
 Looked for pico2.cmake in /home/pi/pico/micropython/lib/pico-sdk/src/boards (additional paths specified by PICO_BOARD_CMAKE_DIRS)

Call Stack (most recent call first):
/home/pi/pico/micropython/lib/pico-sdk/src/board_setup.cmake:28 (include)
/home/pi/pico/micropython/lib/pico-sdk/src/CMakeLists.txt:15 (include)

-- Configuring incomplete, errors occurred!
See also "/home/pi/pico/micropython/ports/rp2/build-PICO2/CMakeFiles/CMakeOutput.log".
See also "/home/pi/pico/micropython/ports/rp2/build-PICO2/CMakeFiles/CMakeError.log".
make: *** [Makefile:45: all] Error 1

In this case, PICO2 was no more than a copy of the PICO files. 

What am I missing here?

[pi-plates]

My bad - I just reread those error messages and realized what I was missing.
Don't try new things when you're tired.