I've learned the process for remotely re centering the STS2 masses.  I played with this on STS2-C.  The attached plot shows my mucking about.

When I first did this you can see CH21 going from -3000 to -10000.  Something less than 5000 counts is centered well enough.  It took a few iterations to get CH21 signal back down and I did a few more so to get CH22 under 3000 counts.  So this works but it can take several attempts.  I'll still be pessimistic about STS2-B which has the mass that swings back and a forth +-14000 counts on each centering.  This one may not center well until something else is done