I use a Holley 650 on my 72 400 engine w Edelbrock performer intake, milled 5C heads and 1.65 rockers...it runs great! and its NOT a racer,its a weekend driver, but i tend to drive it on the hard side...but runs fine in slow traffic and at idle...the 650 "may" be a little too much for the 350, but Im` not so sure...I know the 350 Holley was too big for my old small car which had a 302 Ford in it...(replaced it w smaller Holley and got 19 mpg instead of 12)

maybe just lean it out some?
I get 14.5 mpg at 85-90 (2800-3000rpms) on frwy and about 9 mpg 'having fun' in town...

you`ll get lots of different answers on WHICH carb is better, most people have a preference on make, and when my old carb went bad I asked my mechanic friend (who used to race too)which is best ,his comment:" the one you or someone you know can work on"!
I asked which he preferred to work on...
"Holley"
so there was my choice made!