There is a lot going on here so I've left the pic at full size. Here's the Palmgren rotary table set up on a Craftsman 15" drill press. First let me state that the press is quite flimsy and is barely usable - I much prefer to do all drilling and tapping in a milling attachment on the lathe. But in this case I didn't have any choice.

To drill and tap the 3-56 holes, first the table is made square with the spindle. Then the center of the table is made concentric with the spindle. That done, the part is mounted and bumped around until it is concentric too. Then using the X-axis wheel, I pull the part over the desired amount, which is the radius of the bolt circle I'm working with, or by calibrated eyeball. Then a center drill is inserted and lightly touched to the epoxied disk and a peck mark is made. It's removed and replaced by a clearance drill which is plunged in enough to break through the disk. It is replace by the tap drill and through drilled. It is exchanged with the proper tap and it is started by being held in the hand turned drill chuck. It is a long process, but assures that the tapped hole is perfect in alignment. Next, the table is rotated 120 degrees, locked down, and the whole thing is done again, and again. Fun.