I am very familiar with the proper sight alignment and proper sight picture for several types of iron sights including Buckhorn, Patridge, Peep, Ghost Ring and Tang. In the past year or so, I've purchased 2 rifles that came with Express Sights. Even though the Express sights were removed and replaced with NECG "Peep" sights by the respective rifles previous owners both of them included the original Express sights in the sale package. Some day I may wish to reinstall the Express sights and would like to know how to use them. Intuitively, I would align the top of the front sight level with the top of the rear sight, with the front sight centered in the "V." However, given that these types of sights are on rifles intended to stop a charge I'm not so sure how much actual aiming is done.