I should have posted weights. Yes, I ditched the shelf, striped the fabric, cut off the top and replaced the rickety pins with alum bolts. Hardware was chosen to be durable as I mainly bushwhack off trail.
The frame is made to handle lots of weight, so I can use it for many scenarios.
The 2 tube system = 5 1bs
The 3 tube system = 5 lbs 10 oz
The 2 + double tube = 5lbs 13 oz
The Osprey = 6lbs 13 oz - so in theory - I did lighten my load and added versatility and comfort. The Osprey has such a heavy framesheet to handle big loads - I see some new designs have a hybrid suspension to deal with the bigger loads - alum or carbon fiber U-channels. Looks like things are going full circle: ie back to the framed packs.
I realize this is "heavy", but it carries well and feels like nothing.
Thanks for the input