It doesn't need any more than a 750.What kind??That is up to you.I really like the Holley HP series.I have a couple of the older ones and they have been great.I also have a plain old 3310 vacuum secondary with a milled choke horn and a metering block kit in the rear that has been flawless for 20 years and run on everything from a 350 to a 427BBC to my 496 stroker.
The bottom line is what ever you get you will have to tune it some to get the best drive ability out of it.I had screw in air bleeds put in mine and the tuned on a dyno so I know the fuel curve is spot on.
Your car will run fine with a DP or a vac secondary.The choice is up to you.I still favor vacuum secondary carbs that are street driven more than not.They feel crisper and if the secondary spring is correct you have no performance loss IMO.You can get away with a slightly larger carb this way also without it stumbling around at part throttle in a higher gear.