Bit the bullet and started adjusting the 4f lenses.  The beam profile currently is a
little better than the attached image.  The output power as measured with the power
meter located near the external shutter is ~151W (~148W on the external power meter).
All powers are with the corona aperture in.

    Adjusting the homogenisers and fibre bundle positions did not yield the breakthrough
in output power I was hoping for.