Here is a simple way to skip CRC check. Just NOP [replace with 0's] these two instructions:
0x066C: BNE A3, T0, 0x800001C8
0x0678: BNE S0, T0, 0x800001C8
The emulator will complain about it ("unknown CIC"), but it works.This is useful when modying stuff in the checksum area.
I tested it on a few emulators. Here are the results:
1964 - Doesn't complain at all.
Mupen 0.5.1 - Same (haven't tried MupenPlus yet).
Nemu64 0.8 - One error message ("Unknown bootcode. Chances that this game won't work are high").
Project 64 1.6 - Two error messages ("Unknown Cic Chip" and "Unhandled CicChip(-1) in first DMA".