On a 1ZZFE it can be done. On a 2ZZGE, I remember it not clearing for some reason but that was over 10 years ago. I've done it on the 1ZZFE and it really isn't hard at all. Remove the alternator, power steering pump, belt tensioner, chain tensioner, valve cover, water pump, engine mount, engine mount bracket (bolted to timing cover), crank pulley, crank sensor plug, and crank sensor/AC/VVT wiring harness from the side of the cover. Remove all the bolts/nuts, jack up the motor on the oil pan (with a block), and pry the cover away. Reinstall the cover and bolt everything back up.
I would then remove and reseal the oil pan. I don't recommend removing the oil pan initially unless you have a hoist to lift the engine from the top.
I would then remove and reseal the oil pan. I don't recommend removing the oil pan initially unless you have a hoist to lift the engine from the top.