air strut question....(honda accord)

ok, i got to looking over my struts today, and they have a port at the top for an air fitting and one on the side... now, this confuses me ... are the two ports for if i was going to use an 8 valve setup? like one for fill and one for dump? what if i use the 3way valves and only use 4 valves do i just plug one? and if so, which one is the best to use.. the top or bottom? thanks guys..