Different methods result in different final shape.

I do not have Solidworks here (so I couldn't open your models).

Here follows the process I used in Inventor. Should be the same...

  1. Step 1:

    Revolve this "D"-shape [using the dia.40, R12 and R20 dimensions]

  2. Step 2:

    Make this sweep path [using the R15 dimension]

  3. Step 3:

    Cut this from the solid [using the R10 dimension]

  4. Step 4:

    Pattern this new cut 4 places 360° [4 slots]

  5. Step 5:

    Drill concentric hole [using dia.16 dimension]

  6. Step 6:

    Fillet the edges of this hole [using R0,8 dimension]

  7. Step 7:

    This will leave you with only the 23,9 dimension, which when you measure the two opposite faces will be close to what is left...