It's just been two pieces absent so far. Everything is in sealed bags, so it's an error on their part. They've been good about getting the parts out quickly without question. 
I can pick it off the bench, though I don't know about carrying such an awkward heavy piece down narrow steep stairs to the 'quarry'. I think I'll be walking it thru the house, out the back porch & coming back thru the window opening. 
Worst case, it's just four wires & four bolts to split the u/c from the upper house.