Looks like Gregs manifold has been relieved around the throttle bores a bit.
Perhaps to accommodate a carb with slightly larger than “standard”(2”) 4500 throttle bores.

If Greg is running a throttle body with one large bore(like a flying toilet), I feel like the cloverleaf stuff should def go.
Although, with the plenum area being dry, it may not amount to much of anything.