I am a person who has a difficult time understanding something by just reading it once and enjoys extended time on mutiple choice questions. But, I do well and go fast at math up to Algebra l.
Since it sounds as if you have been approved for time and a half on standardized tests, I think that the time issue won’t be such a big deal for you. You have had your school counselor submit to get you time and a half on the SAT and ACT, right? If not, do this immediately.
I suggest that you take an at home practice SAT and an at home practice ACT, both under time and a half conditions, and see which you do better on, then focus on preparing for that test. In general, it is felt that the ACT English/Reading are easier than the SAT English. In general, it is felt that the ACT is under more time pressure, but your time and a half may nullify that issue for you.