Thermoquad cfm on 340

Awesome questions and right to my point, thank you. I am running A mighty demon 650 cfm dual feed on a edelbrock performer spreadbore manifold with an adaptor. I've been wanting to replace the intake with a performer rpm, but either way i think it,s getting too much fuel. I live and cruise at 7000' plus elevation, if you have any experience with this there is just less oxygen. I thought it might be simpler to go with A small primary spreadbore carb and keep my intake. Thanks.