you can cut off the "hump" if you have a spare cover. if it's your only cover then i'd leave it on. a modified cover makes the process easier and quicker but you can still degree your cam with an intact cover, you'll just need to take it off to make adjustments, then install it again for measuring.
you access one sprocket bolt at a time, whichever is high enough. that means that when you make an adjustment, you loosen the top bolt while the one at the bottom still holds the sprocket in position, rotate the engine until the bolt that's still tightened emerges. then loosen that one, make your adjustment, tighten it, rotate engine, tighten second bolt... you get the idea?
if you ever remove sprocket bolts completely make sure you stuff a shop towel in the camchain tunnel in case you drop them. and before you torque them down for final installation, clean them and also then threads on the sprocket with some acetone, and use locktite.
