Good resources for later Edexcel A Level maths modules

Hi all!
I'm planning on self studying 12 maths modules in the coming year, I've finished 6 and have 6 left to go. The thing that concerns me is that there seem to be very few resources for the later maths modules for Edexcel A level, and I wondered if anyone has found any useful resources that could help.

The modules I still need to cover are FP3, S3, S4, M3, M4 and M5.

I've found a few things about FP3, so that's not a problem.
I'm not too worried about the statistics modules either, since they have been really easy for S1 and S2, and S3 and S4 don't look too challenging (hoping I don't regret saying that now).
I am usually okay with mechanics but I am worried as these seem to be the most difficult modules for most people, so this is where I'd like to find some more resources.

I'll be using the Edexcel textbooks for all of these modules, and so far they've been great. But I just wondered if there's anything else that's useful out there :smile: