Assuming you know about J2EE as you are asking for Part II.
This is what I am doing despite having J2EE application work experience (as it helps refresh some things) :
Understand the UML and Core J2EE Patterns very well. View the Petsore application based on what person knows about UML and J2EE Patterns.
It will help a lot in viewing the Petstore at the high level (say Component Level).
From there a person can go into detail level if it wants. The technique I mentioned may help noticeably in Sequence and Component Diagrams in laying the J2EE components/blocks.
I am using the same technique for my J2EE Part II, though work experience helped a lot. While working on assignment there are very good chances a person can get carried away into unnecessary details not required for Architect.
Understand the concepts and then read the Case Study details in the book you mentioned (from Sun Microsystems) and will see that it gives a very short and meaningful answers.
I will post the results when I am done with assignments.