Glad you got that sorted.
The problem with carbs these days is that different people are rating their carbs in different ways.
They are flowed at different pressures and some are "wet" flowed. Two barrel carbs are rated different to 4bbl carbs etc.
So a 750 demon carb for example flows about the same as a 850 holley. A 1350cfm six pack flows about the same as a 950 4bbl.
I would say that if your carb flows better than a 850 Holley 4bbl then it is probably too big. However if it has vacuum seconday opening then it may be OK.
If the primaries are smaller than the secondaries then that will help too.