early A body engine swap

Yes, they are giving you an option. Umbrella style seals control the amount of oil the valve guide receives
by deflecting oil splash away from the guide. The little cone does the
same thing by preventing oil from flowing down the valve stem
into the guide and are usually used on exhaust valves, (sometimes exhaust seals are just square o-rings) The middle seal is a semi positive intake seal. The two end style seals are really not so much "seals" as they are deflectors. The positive seals usually have a material like teflon that contacts the valve and have a tight fit to the guide, often with a metal spring to retain tension on both the valve and guide.