Can't wait to see pics of your setup, Brent!
In the meantime, this weekend:
1 - I swapped the bungees
2 - I shortened them maybe a 1/2", maybe more
3 - I played with the routing
Stills: 1st and 2nd are with regular routing.
2nd & 3rd - I pulled the tanks forward really hard, and released them gently. The kept settling backward.
On the last ones, I rerouted the bungees (assume an upright position) between the tank and me, and then around the neck and back to the clip. It was a heckofa struggle, but [-]you[/-] *I* can't get them any tighter. Then, (back horizontal) I pulled the spgs forward and held them.