So I threw my toys out the pram and decided to put the callipers and ruler down for the evening and turn my hand to the software side.
I've flashed the Nucleo to the latest version of the MMDVM firmware which should improve performance and fix any bugs that have been fixed since it was last flashed over a year ago.
I also flashed the latest ON7LDS version of the firmware to the Nextion LCD, which has fixed the kerning issue and added a couple of extra features.
|Nextion LCD with ON7LDS Firmware
|The STM32 Nucleo - Note the top two screws are not in the same horizontal posistion