Sorry to hear about your cousin. Great job so far on the rig, which looks to be in good condition aside from the seats! Good move on the reman calipers. They should already have the pistons retracted into the bore--one less tool to buy if you don't have a piston retracting tool. Make sure you have extended brake lines to account for your lift. You don't want them to fail at, or near, full articulation.
I have found OTRAMM's videos to be very helpful--https://www.youtube.com/
@OTRAMM--and obviously, you came to the right forums. There's some seriously knowledgeable and friendly people here!