Your overall breakdown of the structure of the passage looks pretty good, alexisjay. I'll try to answer your more specific questions here.
What does the activist in the 30’s and 40’s being able to predict the reforms that the group of activist in the 60’s and 70’s would try to bring about have to do with the first group being more radical and politically diverse?
Garcia was writing about the group of activists between the 30's and the 60's, saying the were more active than historians previously gave them credit for. Not that they were more active than the reformers ho followed them in the 60's and 70's, but just more active than previously thought. The author cites this bit of information to show that Garcia wasn't entirely wrong, and that he did have some good points and evidence to support them. This server to soften the tone so that it is not completely dismissive of Garcia's study.
Is the author trying to say that while there was political diversity, García doesn’t do a good job of showing it?
That's exactly right! The author is telling us that Garcia not only didn't do a good job on this point, but that he actually undermined himself a little bit. That's one of the two major flaws in Garcia's study, according to our author. He was "inconsistent," meaning his claims appear to contradict themselves.
To be honest, I wasn’t sure how this paragraph fit in at all.
The last paragraph is all about Garcia's other major flaw, an overemphasis on the degree to which the earlier activists represented the general view of Mexican Americans of the period without sufficient evidence to back his claims. The author tells us what Garcia attempts to do in his study in discussing these early leaders, and proceeds to tell us why his attempt is not persuasive.
Nice work on the questions, despite your struggles with the material! I think you had a pretty good grasp of it, despite what you think. Sometimes we come away from a passage with only a vague notion of the details, and that's okay, because we aren't really being tested on those details but on the structure, and the tone, and the viewpoints, and the main point. As long as you can find those, don't let the specifics of the topic get in your way!
Adam M. Tyson
PowerScore LSAT, GRE, ACT and SAT Instructor
Follow me on Twitter at
https://twitter.com/LSATadam