Thanks:)
This game is fully compatible with the original hardware, you just need a custom board, or to find the right donor cart. Though, making a custom board, or finding someone to make it will probably be an easier way to go.
Even if you find an original Shenzhen Nanjing cartridge, there's no guarantee it can be used.
I managed to find 3, and I can only use 1 since it looks like the other ones have epoxy globs over the flash chip.