I had the 625cfm version on my stock 360 in my 79 Power Wagon. First off, you'll need a tune kit. OOTB mine was really rich (was up to 9:1) and I'm only at 3000'. For kick down linkage, have the bouchillon kick down kit. Worked perfect with the carb, no mods required.
The thing that drove me nuts with this Carb: The steps in the metering rods were too large. I could get cruise air good, but then part throttle would be rich. Get the part throttle good, and then cruise was too lean. I probably could have massaged a set of rods to work... really? I thought these carbs were so awesome!?!?
I couldn't get enough accelerator pump shot either. Set it for a quick shot, but right at tip in, it would always have a slight flat spot. Tried bigger nozzles which helped some, maybe I needed bigger yet. I'm not a carb guru by any stretch, but I could get the thermoquad and edelbrock performer carbs to work better. Perhaps the 750 cfm would be a better way to go?
I did use the factory spread bore manifold at first, but later put on a performer manifold with a square bore to spread bore adapter. No noticeable performance gain BTW.
Just my 2¢.