Edelbrocks are really easy to work on. Go to their web site and download a manual for your carb. It'll cover the float adjustment you want to check. Also the air/fuel adjustment and changing metering rods and jets. You may be very rich from the black smoke description and this will require a jetting or metering rods to get it dialed in. The air/fuel screws only adjust idle mix. I had to pass CA smog with my Carter AFB and 460 and it took a couple tries on jets and metering rods to get it within spec.
Good luck.