Grains may be OK in the winter months, but not so good to break a fast with.
i don't use these herbs you mentioned or use apple juice for a pre liver flush. Please read my free booklet for my suggestions.
If you did not eat on the day before the stones are to come out, then your asking for problems and few results. The liver flush must be followed as written unless you know better ways and then it can be greatly modified from Dr. Clark's original flush.
There are many herbs, follow the instructions with the ones you have and you shouold do fine.