The call out is to -A- and -B-. -B- is the 11.00 bolt circle so your position must be taken from that feature. How you add MMC is based on the .375 tolerance. If the .375 width dimension; for example .375 +/-.005 then you subtract what your actual dimension is from .370 and add this to the .001.
For example, the three slots are .374, .3745, and .375. For the first slot, you get .004 bonus (.374-.370=.004) making your true position .005 (.004 + .001 = .005) to the center of the slot. As indicated above, you will need to do the math for each slot as each can give you different bonuses.
Your true position only takes into account the 11.000 basic. The 30 degree basic dimension defines all other positions since the tolerance block of the slot does not account for a 3rd position (i.e. -C-).