I've got a few squares, sold an 86 and an 89 K5 that had a lot of work into them.
Currently own a 1986 GMC 3/4 4x4 with the slow 6.2/TH400/NP208. Bought by my wife's Great Uncle Paul new in the California Bay area. I brought it back to life about a year and a half ago and plan to continue its path back to glory.
Besides that I've got a rust free 73 K5 that is jacked up with all sorts of mismatching lift equipment and a 1985 C10 short bed that is basically a shell. I'm planning on combining these two to make a 2wd 73 K5.