Air Shocks 76 Dart Sport

you want more height!? raising the front a little may give you the illusion of more height to the back... you'll be sacrificing handling, but you've already done that with the air shocks. You can also get taller rear shackles.. a word of caution here, none of these modifications are suggested as good ideas - only as answers to your question.
The +1 or SS springs will net you more height - but they are pricey and not the couple hr. bolt on those shocks were...