Re: Would a gib 496r or bb3 work best with a demon bridge
Fail.
The 496R will be louder and thicker than the Demon. Adding an alnico V may tame the output a bit, but you'll add low end which will only make the EQ mismatch even more drastic.
Keep in mind the Demon is wound to around 10K with 43AWG wire. As far as output, it's only a hair louder than a 59, and has a much tighter low end. Out of what you have, I'd try the BB3 set flush with the pickguard or mounting ring. Ideally, you'd want to pair the Demon with APHn, Jazz neck, or possible a 59n depending on the guitar.