Spidertrax provides really good instructions, so we're not going to get in to detailed installation instructions here. There are additional details and notes as well as some pictures to provide you with additional information.

Tools

Preparation

This is the part you're probably going to hate. 

	Raise and securely support the vehicle. Throughout this installation, save your old fasteners. Some will be necessary for reassembly.
	Dismount the rear wheels. Here's what you'll be looking at. Note that it's the outer set of five (5) studs that are attached to the drums, not the four (4) inner studs.
	Remove the brake drums. Some drums come right off. Some come off with a little persuasion from a hammer and a yank. Some require manly tools.
	When you finally get the drums off, stop and think for a moment. You do not need to disassemble all the brake components unless you find you have good rear axle bearings. If you have good bearings, you'll probably be cutting the backing plate free and will have to remove the brake components to do the cutting. If you find you have bad bearings (like most of us) or if you just want to go ahead and replace them since it's all torn down anyway, then you will not have to remove all the brake components. Instead, you'll remove the whole assembly as a unit after removing the bearings.
	Disconnect the e-brake actuating cables. You can see the lever where the brake cable was attached in the lower portion of the picture here. You can also see that the backing plate has already been released.
	Release all the nuts holding the backing plate to the axle tube.
	Pull the axle stubs (gently, straight out, so as not to damage the seals if they're still good). It'll may require a few sharp yanks with a puller to get it moving, if the bearing is stuck in the axle tube. Inspect the bearings and seals. In the picture at left, the seal is the golden colored ring just visible inside the axle tube. If the vehicle isn't level at this point, one side or the other is going to dump gear oil. Plug the tube ends with rags.
	Inspect the splined ends of the axle for twisting of the splines or other problems. Now's the time to do this, since there's no reason to go through pulling the bearings if the splines are damaged or twisted and the axle stub needs to be replaced. Also inspect the studs on the outer axle ends to determine if any need replacing. Clean up any rust and paint the outer axle ends if you want.
	If you're replacing the bearings, either take the axles to a machine shop to get them done, or prepare to spend quite a bit of time doing them yourself. Gary Munck's friend Walt had the fastest (although risky) method of removing the bearing retainers I've yet seen. He used a plasma cutter to blow away retaining ring material until they were quite thin, then I used a hydraulic puller to pull the bearings and retainers all at once. The intense heat of the plasma cutter helps loosen and embrittle the retainers so they'll come right off (compared to usual anyway).
	Once the bearings are off, remove the backing plate and brake assembly.
	If you're not removing bearings, cut the backing plate down as per Spidertrax instructions.
	Press on new bearings and retainers. This will require a large press. I do not recommend hammering them into place, even if you have a good piece of pipe to use as a driver for doing so.
	Remove your rag plugs and pull and replace the seals (if needed).
	Reinstall the axle stubs, taking care to support the axle as you insert it so you do not damage the seals.

Assembly

	Slip the caliper brackets over the axle stub. The engraved Spidertrax lettering faces inboard. Bolt the bracket in place using the hardware provided with the kit. Torque fasteners to the specs given in the Spidertrax instructions.
	Press the provided studs into the new wheel adapters. There is no "right side" for the adapters, the studs can be inserted from either side. Mount the adapters on the axle end using the original fasteners. Torque fasteners to the specs given in the Spidertrax instructions.
	Slip your scrounged, used or new rotors over the studs on the adapter plates. Back the caliper's pistons out all the way and install new brake pads. Slip the caliper over the rotor and in place on the mounting bracket. Torque the caliper mounting bolts to the specs given in the Spidertrax instructions.
	You're almost done! This is what things should look like at this point.
	Attach the flexible brake lines to the rigid lines from Spidertrax Brake Line Kit (or your own home-brew lines) on the axle.
	Remount the wheels and torque the lugs to spec.
	If you've accomplished everything else (brake lines and proportioning valve installation) at this point, be sure the system is filled and then bleed the brakes. I used synthetic brake fluid when refilling, as I figured the little added expense was worth it with discs all around.

Finishing Up

Test! Use Spidertrax recommendations and test, test, test until you're satisfied that your new brakes are safe. The last thing you want to do is find some overlooked problem when you're attempting a panic stop from 70 mph on the freeway. It may be the last thing you ever do.

If you can't get things right, carefully drive to a brake specialist and have them make it right.