I swapped in the Belltech drop spindles 3 years ago and then put on the Viking coilovers and ditched the torsion bars. I'm not 100% what drop the front is but it's pretty much level or has a little front end rake from the rear 5" drop on 28" tall 275/40/20s on 20x8s on the front and 315/35/20s on 20x11s on the rear. The Belltech offset UCA bushings were suggested and they can help with +/-3° from what I have read. I'm not sure what the specs are now but I am going to get 4 new tires mounted when I order the bushings to see where it puts me and then see about going from there. I don't remember what the alignment specs were when it was aligned but we will dial in the ride height to have a half to three quarters rake front to back and get the alignment and etc in spec to hopefully stop eating up tires. The coilovers do ride and handle alot better compared to the torsion bars a dropped a fair amount of weight off the front end between that and the 2 piece Brembo BBK. I just got the truck back from having the 5.3 pulled and a stock 40k mile 06 LQ9 installed. I have some 243 heads I need to get ported, along with the Fast LSXRT 102 intake I have, with a Stage 2 or 3 BTR truck cam, 4" intake, long tube headers, ORY, a small stall and 4.11 gears. Everything I already have except for the converter and cam because I wasn't sure how far I wanted to take it after the LQ9 went it. Right now I'm just enjoying the extra 70-80hp from the LQ9 over the 250k mile 5.3 that was in there.
Great upgrade with that LQ9! With the 243s and LSXRT, you'll basically have a hopped-up iron LS2 but tuned for a truck. Be sure your head porter isn't just hogging them out. Air
volume doesn't mean everything if it doesn't
flow efficiently. The high compression will make it feel so much lighter. Stay sensible with your cam (sounds like you are) and get an appropriate converter and you won't feel any loss of low-end. I'm looking forward to this build!
Anyway, this thread is about suspension. lol
T-bars, coilovers, air bags... none of these matter in this sense. The control arms dictate where everything is located and how it cycles up and down. You just need to focus on the amount of drop to determine what needs to be done to align it. You can dismiss the 2" drop from the spindles since those don't [appreciably] affect camber. So, for example, if you're 5" lower, then the coilovers are set to give you a 3" drop. You should be seeing what is needed to align a 3" drop. In my example, mine aligned fine with a 3.5" drop just with them cams and still has room to correct for even more drop.
I'd be cautious with the offset bushings. They're a more "permanent" means of adjustment. If they're too much, then you have to try to adjust it back some with the cams or, worse, swap stock bushings (or arms) back in. A member had to do just this a year or two ago. Basically over-corrected for his drop and went all roundy-round trying to get it aligned. He ended up going back to stock bushings.
I really think that, for a 3" drop, you'd be fine with the cams. They're less than $30 and a bolt-on thing. If it turns out that they won't provide enough adjustment, THEN you'll have to move on to more drastic measures. The cams can stay and your alignment guy would liely appreciate them, anyway.
First thing is to settle on just how you want it to sit and get the coilovers set at that height.