I'll be replacing rear shocks in near future on my 2007 6-cyl RWD 4Runner w/~150K miles. It's a pretty straightforward maintenance item as far as I can tell.

Q: Are there any components or items, especially suspension related (e.g. bushings) that I should make sure to inspect or go ahead and replace since I'll be there with car jacked up and wheels off and wrenches out?

Inspect the control arm bushings for the rear axle for cracks or obvious wear. There are lower and upper control arms, they should be pretty obvious when you look under there.

Check the rear axle brake lines for cracked rubber. There are 2 lines from the body to the axle near the gas tank and then 2 smaller lines at the calipers. Replace as needed and honestly, with around 150k miles, I'd replace them as preventative maintenance.

Make sure the breather for the rear axle is clean. It's located on top of the axle, slightly to the left of the center section. Cap will be a little wobbly which is normal.

Not much else to check or worry about under there, just give everything a good visual inspection, issues should be pretty obvious. Wouldn't hurt to change the rear diff oil if it's not been done in a while.

I'll add looking around the rotors for axle leakage. The rear axle seals are getting old. The plus side in your area is no rust to look for.