Flyguide83,
Super glad my post could be of some use to you. Hopefully I can help you further in your situation. Trust me, I know the headache. I too travel with extra serp belts, just one for me though. Actually right now my only issue (considering i'm using a belt that s not too damaged from the whole previous ordeal) is that I get some belt chirp on start-up when the engine, and belt, is cold. The belt warms up and expands much quicker than the engine warms up and the belt ultimately stops chirping maybe two minutes into my cold start drive. Only reason I haven't changed it is cause it that upon visual inspection the belt looks completely fine. I'll change it when it starts chirping consistently after it gets warm, but for now it's not an issue for me. I actually have a 1GR-FE 4Runner buddy who's started down the same journey as you and I too, I'll probably end up helping him out with his accessory drive system here in the next few months.
Anyways, to answer your questions:
1: I didn't formally measure the wobble as you would probably imagine, but I'd say it was greater than 1/8th of an inch but less than 1/2 of an inch. I hadn't necessarily realized it till after I'd changed almost everything else.
2: I'm not sure how versed you are on your garage mechanic skills, but I'd put it in the same bracket as changing a wheel hub assembly, but definitely doesn't require as much force- so ultimately easier than that in my opinion. I bracket them together because if I could've gotten a slide hammer into the space of my engine bay, it would've made the job move a little quicker than the pulley removal kit I used. The only "difficult" part was installing the new pulley. Take your time and be extra meticulous and firm when installing the new pulley. Before you pull the bad one, measure at various points on the pulley to the block and find some sort of clearance reference, and find consistencies. When you go to install the new one, it is imperative you install it as flat against the block as possible. Depending on how nice the pulley installer tool you use is will kind of help determine how easy it is to get a consistent push on the pulley to get it installed flush. I used a dinky spirit level to ensure mine was flush but it took me a few off and back ons to get it on right. If I was more meticulous my first couple times around I probably wouldn't have had that issue but I'm also super apt to learn about all these things as I go and I'm glad I can help people like you later down the road! As far as removing things is concerned, It sucks but you're gonna have to remove the radiator fan shroud and potentially the radiator fan. I believe the maint manual suggests removing the fan as well as the fan shroud. I tried accessing the pulley with the fan still on and it was a royal pain. I ended up removing the fan- which was another royal pain- but I believe I was able to properly access the pulley (physically with all the tools and whatnot) and get the bad one off and the new one on in better time than if I tried the entire process with the fan still on.
Know that as you go about changing pulleys, though you may find one that is obviously bad, if you just change that one, it's going to bring out the discrepancies in all the others. I firmly believe this is part of what caused my crank pulley to go ultimately, but I'm not a mechanical engineer... that's just my honest opinion about my observations as well as those of others. It's helpful because ultimately it'll help you properly diagnose bad pulleys sooner but it's kind of fatiguing to be working on the accessory drive system every weekend or so. As i started changing my pulleys out it got to the point where I was shredding serp belts and changing bad pulleys every weekend or so for about two and a half months straight. Good thing now is I don't have any more issues other than my cold start chirp due to what I believe is a prematurely worn belt but I've accepted my fate and have a backup serp belt for when my chirp becomes way more consistent.
Hope this reply was more helpful than it was long winded HAHA!
Feel free to shout at me as you continue on, I'm more than willing to help you out as best I can.
- whigglets