yep.. there's a good chance those rear lower shock bolts will be seized. i had to drill mine out.

also, find a way to reuse your stock dust covers if you can, or some kind of dust covers. for the koni shocks, you'll have to widen the hole of the stock covers so that they fit over the shaft. they may not fit with the GC sleeves though, but it's a bad idea to run shock shafts exposed.

and you will also have to find a way to secure the brake line with koni shocks. i removed the brake line bracket (yes it's a seperate piece), from the stock (front) shocks, and set them onto the konis. (edit: which you're actually supposed to do, that bracket also keeps the lower fork in place). again, i'm not sure how this sets up with the GC sleeves.

otherwise, it's not exceptionally difficult. make sure to torque everything down under load.