The forum post linked early on has the nitty gritty on how the actual binaries were hex edited to no longer need the unsupported opcodes. He manages to do this

The forum post linked early on has the nitty gritty on how the actual binaries were hex edited to no longer need the unsupported opcodes. He manages to do this by rewriting the XP kernel (SP3 version towards the end) but does reference how the 2000 kernel did some functions without the instruction along the way.