In my experience , its almost easy with the size of bolts we use. I have done structural steel for over twenty years. With structural pieces and stairs we would sometimes have to tack on nuts for a blind connection , usually tight in a corner where the wall prevents the connector from getting a hand in behind to hold a nut. The size we use is almost always 3/4 inch bolts and nuts.
I use a 3/4 inch flathead bolt , set-up for a countersunk hole. It has a round head , and is set-up to be used with an allen wrench. Our holes are usually punched , if not I drill the holes , then put the bolt in with the tapered head on the opposite side of where you need the nut , the taper will center the nut in the hole. I just hand tight the nut , just to keep it from wobbling. Then a little shot of spatter spray , I weld two opposite sides of the nut . I dont need an allen wrench to loosen my bolt , because i welded a handle on it , it gets hot after a couple of holes. Hope that helps......c