Congratulations that sounds great.
I used to use 3 evenings of Oxypowder before the flush, now I might use Epsom Salts (1-2tsp) or some magnesium citrate a few days before. I feel like you I like to be clean by the time I do the flush, you mainly then get water out and not BM, so you can see everything clearly float.
The other day I decided too late and drank a bottle of magnesium citrate on the morning of the flush.