Ahh So'
Hmm' Maybe he needs to not buy one more and to maybe run his one on a good single plane. 750 DEmons are good carbs once tweeked in for the needs.
Depends on which 750 DEmon he has if it will work right on a tunnel ram. He will need a high rpm engine with more compression big cam etc for even a good matched pair of tunnel ram 750's to work good though.
By me looking at the compression he is talking about my voice says no, don't do it.
Do either your 750 Demon on a Good Inatke and enjoy it and the response and power you can make with it, after it is correctly tuned in, or buy a paior of matched 450 cfm carbs to put on a tunnel ram and enjoy the looks and the performance with those.
Ed