You're averaging 13,000 miles between front pad changes. This is rather low life for pads, but it may be normal if you drive in a hilly urban environment. For my car new pads are 11 mm thick. It contacts the sensors at 2.5 mm.
As you said, with pad replacement you simply reverse the disassembly procedure with new pads. Like Larry said, do one wheel at a time -- you might find yourself in trouble when you push back the caliper piston with the other calipers unmounted.
The scored rotor is worrisome. You shouldn't put new pads with badly gouged rotors. Replace the rotors in pairs (both fronts).
Ditto on flushing the brake fluid afterwards.
How do you plan on checking the wheel bearings? If you're only checking for axial play, be very careful not to let any grit into the grease cavity. Anything more will require you to completely clean the old grease, regrease with proper amount of new grease, replace the grease seals, and properly set the axial clearance. Sometimes it's better to just leave it alone.
The center bearing cap can be coaxed off with a blunt wedge - such as a cold chisel - and gentle hammering, then pried off with a screwdriver.
95 E320 Cabriolet, 131K