Some notes from my (incomplete) experience. Working alone, I spent 5 long evenings removing the transmission (2004, SC, 4x4); I'm not particularly fast but as OP suggested, it is a lot of complex work.
OP asked early on about removing the "sheet metal" which is also called an inspection plate, my FSM calls it the "rear plate cover". To remove this, as it says in the FSM, you have to remove the 2 gussets connecting the AT to the engine on each side; 2 bolts on the transmission, 2 on the engine for each gusset. I don't believe you can remove the bolts "through the starter hole" as was suggested; you have to remove this plate.
More recently, posters mentioned pulling the wires out of the crankshaft position sensor. I read these posts before pulling the AT and still ripped the wires out of the sensor. I thought they were talking about the "turbine revolution sensor" which I now realize you don't have to pull out; you disconnect the wire harness from under the hood and the wires come out with the AT. The CPS is hidden behind a metal plate (looking from aft); another plate on the same bolt holds the driver post cat O2 sensor (which I almost ripped out because I didn't know it was connected here, might have damaged the wires). The FSM doesn't mention the CPS in the transmission chapter. My Chilton manual mentioned it but I just thought it was also talking about the TRS.
You don't have to remove the TRS (or the revolution sensor) like I did. The wire for the CPS is so short, I'm not sure I could have avoided pulling them anyway. You may be able to crawl on the engine and unbolt it from above. I'll snoop around to see if I can gain some length in the wire by removing plastic mounts, if not, I'll solder more wire. Or better, I should just put a connector there.
I avoided removing any exhaust components by removing the transfer case first; the FSM said to pull the AT and transfer all together, Chilton said separate them. The passenger cat did get in the way a lot; I couldn't get the cooling lines out and the dipstick tube was difficult to remove because of this. I was able to rotate the longer cooling line out of the way like Scott shows in his video above. If you want to minimize exhaust work, maybe just remove the passenger cat. The driver cat and the y-tube rarely got in my way.
Sitting on a transmission jack, it took some manipulating to get the transmission from under the vehicle. The front of the vehicle was on jack stands at the highest setting; I put the floor jack on the rear axle and lifted about 19 inches.
I played a long game of Tetris to remove the starter. It ultimately came straight down. I wanted to leave it up there but it kept interfering with me trying to Jenga the cooling lines out which I never accomplished.
Over the next few days I'll rebuild the transmission, resolve an oil leak (I hope it is the rear main seal), maybe change the post cat O2 sensors, paint the oil pan (rust caused by a head gasket leak under the manifold which I just found while toying with the starter), repair the sensor connector, etc.