Brakes

Might be a little late, but a top tip when changing brake lines is to place a sheet of cling film over the brake fluid reservoir and then screw the cap back on. The caps are vented so if you disconnect a brake line without clamping it off the system will drain down. The cling film creates a vacuum in the system and buys you precious time.

Can't stress enough how important it is to not allow the reservoir to drain down too far when you're bleeding. I once did that on my old Z3, I drew air into the abs pump and no matter how much bleeding I attempted, it made no difference. I had to buy/download the BMW service tech software onto my laptop so that I could activate the abs pump in order to 'purge' it. Nightmare!!

Slowly slowly easy monkey is the best bet when bleeding brakes

Watched an edition of wheeler dealers last night and the mechanic Ant was doing brakes on some hideous yank monster.....after he'd bled the brakes he needed to reset the ABS pump which required a setting with a laptop and a bleed nipple ...
Don't know if this is relevant to a Gen 4 but I'll stick to my 1980’s bikes and my non ABS Jimny ta! So much easier.