What will it run?

I know it is a miss-match of parts.
When I was re-gasketing the motor I was going to throw the 2bl back on, looked over at the shelf and decided to grab a 4bl intake and carb.
I have a 750 holley set-up for blowthrough, a 750 holley d/p, a 1000cfm comp. series thermo, 2 bigblock, and 3 340 thermos all rebuilt. Intake choices were a choice of 3 71' 340 intakes, 3 72' 340 intakes, ld340, tm5, and a couple 2bl intakes. The tm5 had the smallest ports. The carb was one of the first thermos I built for the duster, flows a little over 840cfm. Threw some small jets in it and decided to see how it would do.
A buddy has some carter 600 340 carbs I will try next. I don't really want to throw any money in this, just want to get as good as combo as I can with whats at hand.