Hello All ... Closing the loop on this thread.
Spoke with my dealer and there is an adjustment (see pic below) that sets the upper limit. You can go as high as where The lift arm would hit the bottom of the hydraulic cylinder - you want 3/4 of an inch for play.
By shortening the linkage it allows more movement so it goes higher. I still have a little more room if I decide I need it.
Simple adjustment, now that we know what it is ...
To all the comments and questions, thanks for that, it helped me think through it all and narrow down the possible solution and eliminate the simple but not so obvious items.
To the person that said that my expectations were out of synch with reality and I should just buy a different post hole auger - bless your heart and thanks for playing.