To edit the assembly code, use IDA pro 7.2 and do your changes there, that way they can be backed up easier. There are a few misceelaneous commands for the processor. Output your file via the LST file ...
Note: This project was renamed from nesgodisasm to retrodisasm to reflect its expanded support for multiple retro systems beyond just NES. retrodisasm is a tracing disassembler for retro console and ...