I've just been through the FAA process, but have been EASA & CAA licensed for +30 years. The FAA system is more General Aviation based and Digital systems and integrated avionics such as ATA Chapters 42, 44 & 46 are hardly mentioned. However, the books you mentioned are pretty good as purely basic system descriptions and a good starting point for where you are at. FAA AC 43.13 is also a pretty good source of info on "how to" do the job especially around repairs.
I would treat the questions purely as revision aids on how a system works. Pt.66 knowledge and standards are deeper and broader and more up to date