I pumped up the launcher to 70psi, loaded the ball, launched it almost straight up. I fired the tennis ball up over some tree branches at about 60'. The ball went up, cleared the branches and easily came down the other side. I attached some heavier line to the far end line and pulled it up and over the branch. I pulled down the PVC and attached the center point to heavy duty rope. I then pulled the center point back up. The launcher worked great and my next step will be to raise the end points from 10' to 20'.... which will allow me to then raise the center point a few more feet.
I had two 20M SSB QSOs: a station in the British Virgin Islands that gave me a 59 and a station in Italy that gave me a 57. I'm pretty comfortable that my antenna is working at least as well as it was before I made the changes.