Last two pictures of Navy sluff are taken 1990/91 during DS. At the time Sluff was ready for retirement...and VA had not enough pylons at the moment, so pylons from stations 2,3,6 and 7 were didided for two aircraft. Except HARM birds.
Second pic- empty station 6 may indicate that mission was carried without it and flight was refueled on route.
In real unlike in game pylons are not something that you plug and play on a whim..it takes time to wire systems and pylons..and during combat deployment not always there is a time for it. Often aircafts wired for HARMs stayed HARM bird for whole deployment while other birds were bomb trucks with TERs. Also from certain point ..if you have TER fixed to pylon and mission requires smaller payload - you just hang one mk82 on TER...it saves time too.