If you're going to be opening up the top of the engine, get an extra torque wrench in inch-pounds as well as having one in foot-pounds. I have an inch-pound torque wrench which ranges from 25 to 250 in-lbs. Many of the bolts which attach to the valve cover are torqued very lightly, like 31 inch-pounds for the bolts which actually hold the valve cover on. You definitely do NOT want to go 1/4 turn past tight with those bolts -- you might get away with it a couple times, but it's not worth the risk of cracking the valve cover.

I haven't come across anything yet which required torque in excess of 100 ft-lbs.