Hey,
So the source analysis isn't as big as what you'd do in Modern (I think, I don't do modern). It's 600 words max, so your looking at around 200 words each, but one of mine was bigger then the others. You need to do your three most valuable sources (so for me, that was my historians books, and a youtube lecture on the topic). You basically have to comment on the strengths/weaknesses, reliability and usefulness of the three sources.
So, some of the things that I look at for reliability I looked at their:
Academic qualifications (one was a professor at Harvard)
Methodology (if they used a lot of sources, one was selective in their use of sources, etc.)
Biases (one had a father in a concentration camp)Usefulness:
How it had helped me in terms of the project (what I did and didn't get out of this source for my essay)You've also got to make sure that your making a judgement thought the source analysis on the reliability and usefulness of the source (I think the A band was makes a sophisticated judgement)
Hope this was helpful! Good luck for the project!