semperfi96, welcome my brother in arms. As for installing the torsion bar keys, it can be easy, it can be hard. It really depends on where the truck has been driven and how much rust you are going to run into on the underside of the truck. PB Blaster and a BFH is going to be your best friends for something like this. To do this job, this is how I would handle it:
-Squirt the bolts for the torsion bar adjusters, the hex joint where the torsion bar meets the key, and the other end where the torsion bar meets the lower A-arm.
-Measure (or count the threads) the bolts on each side for the adjusters so you know where to restore the bolts to so you keep the truck level.
-Put the front of the truck up in the air supporting the truck by the frame (not the lower A-arm) on jackstands.
-back off the bolts for the adjusters till the keys are just above the block that the bolts run through
-use a large C-Clamp and take up a little load of the key
-remove the bolt the rest of the way and then slide out the bar the bolt ran through
-back off on the c-clamp and remove the tension off of the torsion bar.
-spray the ends of the torsion bar again with PB Blaster
-Using a large punch and a hammer (the bigger the better), remove the torsion bar from the end up at the A-arm, then remove the torsion bar from the key.
From here, reverse the steps and reinstall everything. You will find installing the keys is going to be a little more difficult since you will need to put more preload on the torsion bars due to the new keys. But, not that bad overall.
As or the rear spacers, the steps are as follows:
-place the rear of the truck up on jack stands with the jackstands on the frame of the truck.
-place a jack under the pumpkin of the rear axle and apply a little bit of upward force (move the axle up about 1/2"
-remove the tires from the axle to allow it to drop (or you could have initially set the jackstands up where the rear tires were about 4+" off of the ground).
-undo the lower mounts on both shocks and disconnect the shocks from the axle
-lower the jack down some to lease the pressure on the coils, once loose, remove the coils from the truck and continue to lower the axle down another 3" or so to account for the coils and spacers for reinstall.
At this point, reverse the sequence and you are done. It may be advisable to get different shocks since you will not have a high chance of maxing out the shocks, leading to potential damage to the shocks since your truck will be sitting higher. Depends on how much 4x4ing you do.
Granted, could have saved you a lot of time, you could have bought my truck. It already has a 4" lift and 37" mud tires on it. I don't have the need for an SUV any more (kids have moved out of the house), so, I am moving on to something a little bit different. What that will be is hard to say. Got 3 different paths I am looking at for the moment.