Re: Few questions..I didn't undertand from Clarks method.
If you start on a Friday, you'll drink the olive oil on Saturday morning. The actual process of taking the drinks lasts from 6 PM one night, to about 8PM the next morning, with several more bathroom trips after that. So if you have weekends off, you could do it Fri or Sat, and be perfectly fine by Monday.
The hours suggested are a guideline, and the spacing between them is most important. That being said, I would hazard a guess that it would be ok to move everything back an hour or two and still get good results. What I mean is - instead of 6 PM and 8PM ES, 10 PM OO/GFJ, and 6 AM and 8 AM ES, you might be able to do 8 PM and 10 PM ES, midnight OO/GFJ, 8 AM and 10 AM ES. As applies to many things here, it's always good to customize and tailor these cleanses and flushes to your own personal needs. You might find that this works really well for you.
I never tried ornithine, never needed it, so cannot answer that one. Good luck with your flush.