The gm dampener wobbles, some times excessively. It is often replaced with after market. I went with a ATI super damper. There are others such as powerbond - I have no experience with that brand.
AC wise, the pulley is not touched. You do have to pull the AC condenser bending the aluminum lines which is uncomfortable. If not present already, I recommend installing the revised double idler/bracket for the AC belt now while you have the front off.
Not sure if you mentioned it but I recommend picking up a valve spring tool if you don't have one.
I went with the crank pulley from Summit as it was cheaper than the ATI balancer and appears to do the same thing, albeit as a 25% underdrive. No issues with it so far. Different sized belts are required but Summit supplies part numbers with the instructions for the belts. The crankbolt that comes with the BTR kit is an OEM bolt, not ARP, fyi. You technically "can" run the pulley in with the old bolt but just get an installer and play it safe. I'm not a fan of potentially damaging the crank threads. I didn't use a flexplate holding tool, just wedged a long prybar through the inspection port at the bottom of the bellhousing. Not ideal and kinda wonky but it works. Wish I had the holding tool to he honest lol.
Electric ratchet is fine for most bolts but some are a pain to access. A flex head long ish handled 3/8 ratchet works well in those cases. Various extensions both 3/8 and 1/2 drive are helpful.
2 of the biggest mistakes I made along the way were putting the flexplate on backwards (I didn't make sure it rotated after I installed it and had to pull the motor again to fix it). Not a huge deal but took another hour or so to correct.
Other mistake was forgetting to put the lifter tray bolts on. And finding the bolts on the workbench after installing and torqueing the heads. I ordered my BTR kit with oem headbolts so my brand new bolts needed to be replaced again. Ordered ARP bolts and corrected it the next day. Hooray Amazon 1 day shipping.
Get yourself a decent sized drain pan. Stuff leaks from everywhere and power steering and trans fluid leak quite a bit. You can get a large cement mixing tub from homedepot for around $10, perfect for sliding under the car and catching all the drips. Or just find a way to cap the lines. Don't forget to too off the transfluid as well (presuming you already will since you're doing the converter).
Also your long tubes "should" come with two O2 sensor harness extensions, mine only came with 1 harness so I ended up having to find one on my own.
Best of luck, take lots of breaks and don't make stupid mistakes like I did lol.
I like to take a cardboard box or large flat piece of cardboard, and make a crude drawing that matches the perspective I'm working on. Then just punch holes where the bolts go, and put them in there. It might take more than a few minutes to do, but certainly helps keep track of things IMO. Good luck and have fun, quite a list of parts you have!
Are they stock bolts in your kit? In some ways stock bolts have held for ten years without leaks.
Now if I was adding a blower, ARP head studs or bolts would be a must. Now cam bolts, not a high stress location like a connecting rod bolt. I would add blue loctite to the bolts. Is the IWIS chain part of the timing kit?