They clear just fine with 1.6's or 1.7's, only issue that arises is since Ford cuts holes in both sides it is in the way of many of the EFI manifolds, even with the thin billet filler cap that someone sells. It is to close to run a breather on both sides so, except on the Victor 5.0.
I have been getting the Moroso covers for motors I build for others if they want the tall polished look. You cut the breather hole (no holes drilled in either), it comes with multiple grommets and valve cover studs and they are identical but have no logo. I also make baffles to go over the breather hole using the cast in bosses or it tends to spit oil out if using a open element breather filter.
Here is a pic of a motor/car I did last year, the Holley has a 1" spacer and a modified plenum to clear the covers...