bilstein doesnt sell their 4600 shocks as a loaded assembly.
+1. I opted for the 4600s myself, as I have no desire to lift the truck.
I used two spring compressors at a time, per coil spring. Two reasons, one, they help each other, so all the load is not on just one. Two, if one fails, the other is there. I believe many manuals tell you to do it this way.
I had to buy a good grinder to cut off the top shock bolts, as they were seized on there. Stripped out the factory threads trying to get them off, no amount of rust-killer or penatrent would bulge them. After struggling with the first one for hours, it was quite satisfying to simply take a large cutting wheel and chop the stupid nut into pieces. Luckily, I had planned for this contingency, and had also bought two new upper strut mounts. I didn't have to worry about preserving the factory upper mounts, which are easily damaged when trying to cut off the recessed nut.
Pre-assembled struts/springs would have been easier, but definitely not cheaper. I drooled over the Fox assemblies for a while, but when you can buy all four Bilsteins for the price of one Fox assembly... I made the economical choice.