I'm with VehiGAZ. The rear bolts just aren't that hard to get to. Granted, you won't be able to get a socket on the nuts, but the newer ratcheting wrenches or standard ones will get in there just fine. I did it with a non-ratcheting 19mm wrench because that's all I could get my hands on. While one of the top nuts was particularly difficult to break loose (even though I sprayed them down liberally with penetrating lubricant first), accessibility was not the issue. Navigator has the right idea - it is all about getting enough leverage on it. My wrench was a crescent on one end, closed circular on the other end. I finally got it by interlocking an adjustable wrench on the open crescent end of the wrench I had been using, effectively doubling the handle length I had, and I made pretty short work of it then.
I do not understand why people say the exhaust side (left rear) is difficult. The nut is accessible enough unless maybe you're trying to get a socket in there. If you have one, use a 19mm ratcheting wrench to make things way easier on yourself. The left rear top bolt backs out with no obstruction. Here's a pic:
The reason I mention the clearance for backing out bolts is this - what was a little tricky was the right side top bolt. Rather than any exhaust sytem obstruction on the other side, I think this is actually the problem PeteVX is remembering. When you have it just about completely backed out, it hits something. I had to work with it for a little while and wiggle it a bit and finally got it free. Here's a pic, with the obstruction area indicated in red:
Finally, here is why the advice mbeach gave about clearance is worth noting. You can see that it would be a problem to mount the rear shocks with the adjustment knob facing rearward, where it may contact the shock mount. Hopefully no one would manage to do that though because you should realize as you're doing it that it would be hard to get to for adjustments and see it's a tight spot. Here's the pic:
I had a very difficult nut to break loose on each side. For me, the bottom right rear nut was tough, and the top rear left was as well. The other two went pretty easily. Again, access wasn't the problem - they were just damn tight and hard to break loose even when sprayed down with lots of WD-40. Leverage is the key. On tough bottom one I encountered, I actually used a 3/4 standard hex 1/2" drive deep socket on the end of my torque wrench. It is a 19mm bolt head but that socket went on it nicely with no slipping. Essentially it gave me about a 2 ft. breaker bar. It still wasn't a piece of cake, but that made it much easier than it otherwise would have been.
Contray to what many have said, when it was all said and done, the rears were much easier than the fronts for me. I removed the front wheels for improved access to the front shocks. That is not necessary for the rear shocks. Also, the front shocks had some fight left in them so I needed to use a pry bar to compress them enough to get the studs down and out of their mount holes. Eye loops on the rears made them pretty simple to deal with by comparison. VehiGAZ said it and it's true for me too - once you've done it once and gotten a method down, you could go back and do it again much faster. The main thing I'd say is please be safe about it - use a good jack, choose good sensible lift points, and put a jackstand under the axle as backup just in case.
As for my impressions, they seem like very well built, quality shocks. I used the red urethane Rancho bushings rather than replacing the stock rubber ones and would recommend doing so to everybody. I just got the rears in last night so today was the first day on all four new shocks. So far I have only driven with the shocks set to the softest setting. One of Hotsauce's posts somewhere recommended this for breaking them in. Not sure it makes much difference, but I figured I'd do it. I can say I don't like that setting much, but don't take that as a knock against them yet as it is the very softest setting. I have cranked them up some and will go out and see how I like that.