The SC400 1UZFE doesn't have the oil pan gasket so I think the LS with 1UZFE is the same. Taking out the oil pan with the silicone sticking isn't easy. Using the electric heat gun and lightly heat around the oil pan edges to melt down the old silicone. Slightly tap the oil pan and you can remove it in 5 minutes. Make sure don't heat up other components. After prying off the gasket residue, you can use acetone to finally clean the surfaces.
The high temp gasket maker silicone is a quick way to reseal it. You only need to put the silicone on the lower oil pan surfaces and there's no need to put it on the upper section. Be generous about the silicone bead of at least 2mm thick. It's better to have it sealed with the silicone falling out of the edges rather than re-doing it again. While it's stil wet, you can clean it up afer tightening the screws. For tightening the screws, it's better to start from the center, going X section to the other side and back. This pattern will make the X wider everytime. Don't torque the screws too much. I can only feel it by hand now. But if my memory doesn't betray me, the torque may be 10-12 ft/lb. Follow the dry time instruction of the silicone and you're set.