Here is a hard-to-find, cost-saving fitting. A PVC 3" x 3/4" reducing tee costs about $10. These tee eliminators can do the same thing for under a buck! Just drill a hole, press in a tee eliminator, then thread in the connection.
Made of flexible PVC with female pipe threads. Works in all rigid pipe materials with pipe walls between 1/8" and 1/4" thick.