Before proceeding, I nudged in each of the slits, watching for first clipping. With the current emittance (nice), the beam cleared both slits completely; the upstream slit began clipping at about 1.5mm, and the downstream one at about 2mm. Also, FC6 current with slits in/out was: ~30nA / ~57nA. Note: I had to change the scanner parameters a little.

Data file: 090810_1648ILTEMIT.txt