Little bit more done today. Got all connections/etc. disconnected so the rear subframe is completely out. Driveshaft removed. Mid portion of exhaust removed. Rear ABS sensor wiring removed (For good). Muffler heat shields removed. Just lots of little misc crap removed basically.
With the underside fairly exposed at this point, I was actually pleasantly surprised by how little rust there was considering this thing has over 160k miles. Mainly just in spots where the rusty fasteners were, are little spots of rust. However I was inspired by this project:
I don't have the skills or patience to go to that level, but still, makes me want to get the underside of the car looking nice too. So I will be trying to take my time and replace anything rusty (fasteners, clamps, lines, etc). Coat things like control arms, subframe, diff, etc so they look like new again. Replacing bushings with poly ones where it matters, and probably just OEM in some spots to keep it feeling like a Lexus. And may consider sanding and putting some sort of undercarriage coating, but not sure yet if I'll take it to that level.
Here's how I left it tonight, as well as some shots of the underside of the car showing the small areas of rust around fasteners.