nannan66

Relied on Schweser only and did well on level III.

I would advise choosing the set of books that you consider to be most well-written.
Your thoughts will be drifting off - no need to encourage them with lengthy prose.
Stick to a reading plan and spend lots of time on questions, cards and as many clocked practice exams as possible. The same strategy as for level II, really, even though the exam is very different.