This morning, with Hugh's help, I went into BSC1 and unlocked and rebalanced the ISI. Rather difficult, as I had to use the masses on the side of St2. At one point, I had to cram my body as far up into the dome as I could physically fit to remove mass off the top-most mounting points. The floating position looks good, and the ISI is currently unlocked (per Betsy's instructions), but the lower stages of the quad are locked on the barrels. Will try for Tf's tonight, if possible.