You do know that those LCAs are for a 73-76 A Body with a sway bar? They will fit and install on your 66 no problem; however, the sway bar tabs are in the wrong place. They should be out at the end like this one:
Yes, I'm aware of that. I don't have a sway bar anyway so I'll either be getting that from Jesper (who sent me these, he has that too, it was just a little too bulky to ship) or making my own. As far as I know, the original bar is pretty flimsy.