I'd get the 34-105 kit which comes with a pair of blocks.
Several years ago I built a few "HP750's" out of the original ProForm bodies.
Back then I just used std metering blocks for a Holley 4779(750dp), along with std base plates.
Those carbs worked pretty well....... So I thought I'd do another one with the new style parts. I used the Holley HP body for this one, along with the aluminum qft bowls, billet baseplate, and the 34-105 metering block kit.
Unfortunately, I haven't run it on anything yet, so I can't comment on the performance.