Rear shock mount extender:
looking up and slightly back at the left side rear shock. Upper left hand corner is the spare tire.

https://cimg6.ibsrv.net/gimg/blazerf...82b0fc0374.jpg

Alignment after suspension lift and installation of idler arm:

Edit: Note, upon later discussion (see below) we decided that it was not that the caster was not adjustable but rather that the caster was able to be adjusted because of the lift.

https://cimg5.ibsrv.net/gimg/blazerf...9f818e2a5e.jpg

Nice and straight

I wonder why caster wouldn't be adjustable. I have a solid axle under mine, so I can't really refer to it but, from what I can see in your pics, it looks like it should be adjustable. It should just be a matter of adjusting the UCA bolts unequally to adjust the angle of the control arm (and the front to back position of the upper ball joint). Am I missing something?

TomA,

Good point. When I was told that, I just accepted it. Your question had me look in my GM manual and sure enough, you are correct.

Digging into my records I found another alignment done immediately after I did the suspension lift and found a note that they were not able to adjust the caster. I must have misinterpreted I was told; Instead of the caster not being adjustable, it was that for some reason (because of the lift?) it was not possible to adjust the caster.

It likely is that they could not get it within specifications given the amount of adjustment required versus the amount of adjustment possible. There are limits to the amount of adjustment in the cam bolts/plates.

Swartlkk, if you say it is so, it must be true! :) :icon_imnotworthy:

More seriously, it is nice that my guess as to the limit of the caster adjustment was not off-the-mark.