Z20 mount height for Onefinity Elite Foreman

What height should I install the Z20 frame on a Elite Foreman for a 80 mm PwnCNC spindle? For the Makita router with a shim I used the lowest of 4 sets of holes.
I am using the Suckit Dust Boot which has arms that connect to the slots on the Z20 frame, if that makes any difference.
I will be switching to the PwnCNC V8 dust boot which also uses the Suckit support arms as soon as I get the spindle mounting height figured out. Are the PwnCNC Z-Independent Bracketing System arms any better than the Suckit arms for connecting the PwnCNC V8 to the Z20 slider?

To my knowledge theyre not compatible. Our arms are straight down, where suckit are projected forward.

Given your going to use a z independent system, the lowest holes will work just fine. The lower you mount your z axis, the higher you can mount your spindle and cover the same area, the higher you mount it, the lower you’ll have to mount it to touch the wasteboard.

You’ll also create a distance the higher you mount it as it regards how low the arms will reach

Thanks for the information.