The old hub has the large center hole for the nylon pitch change cylinder. Photo of my "B" hub anodized a gold color is shown below. Hubs thru Rev "D" all have the large center hole.
I didn't take a photo of the new hub. I have included Van's assembly drawing of the new design hub which shows the three (3) small holes aligned with the prop axis. The new design started with Rev "E" and includes latest Rev "F".
Large center hole - Rev's thru and including Rev "D"
Three (3) small holes aligned w/ prop axis - Rev's "E" and "F"