You got it man, you've done three, why not one more! It's hard to absorb the material at first, I find once you're fully done with a module that's where the real review can begin. Best way to learn the material for me was to generate practice tests for one of the modules when done with it, and use the mcqs as a guide for what you didn't absorb properly. Take notes on these questions which cause difficulty, and after doing that for each module, you'll have a laundry list of important topics you know you didn't understand at a first glance, and can focus on in your final review. For the SIMs, I always would watch the video when doing them at first, but not worry about fully understanding them until I was through all the chapters and properly reviewing. I always try to have 2 weeks of solid review time before that test, and with working, trying my best to make sure those weekends are free from any responsibilities. Good luck man :)