[My427stang]

I'd run a 950 HP as a minimum, but would advise you go with a 1000 HP Holley or an 850 Barry grant or 850 QFT

The 950 is a misnomer, its a 750 with an 850 baseplate and isnt a very big carb for what you have.

I run an almost identical 489 FE in my 3500 lb Mustang, with an almost identical running gear and run an 1000 HP series carb, it is very streetable and very much not fussy.

The 1000 is actually dimensionally the same as an 850 asides from a shaped entry area, and remember an 850 isnt out of place on a heavy 454 or 460 with an automatic in a full size car or truck. I promise you have enough motor to happily use a good 850-1000

The 950 is a good carb, but it is smaller and will lose top end charge, but gain you nothing down low over a modern 850 or 1000 HP.