Don’t waste a lot of time or money on CFRs. You use them on the 70% sections.
You can pass those 70% sections in your sleep. There is a lot of room for error. You could fail every CFR question and still pass. You have a 25% chance of blindly guessing the right answer. You can make an educated guess on many questions which improves your odds to 50/50.
You could simply memorize the answers to the CFR questions in the test bank, and get the majority of them right without looking at the CFRs.
You should find someone to show you how to use the CFRS and spend maybe one day on learning how to use them. You should be able to find CFRs to practice with at a school or library.
Spend 90% of your time on the 90% modules: RoR, T Nav, and C Nav. I don’t know how much time you’ll need to spend on the new stability module, but probably quite a bit. The chart plots are worth spending some time on. You should be familiar with each of the charts.
A few years ago, I sat for three additional licenses. I got the approval to test notice about two weeks before I was going back to sea for several months. I only studied Rules of the Road. I just winged it on everything else. I did 15 modules in three and a half days. The only thing I didn’t pass was C-Nav. Of course, I’ve been around for quite awhile, learned the material the old fashioned way, and actually used the antiquated stuff back in old days.