I used to have an SP-1 that flung the cases either into my right earlobe or right cheek every time. A friend and I swapped parts out of his old 5*** SP-1(1965-vintage, I think)but nothing stopped the rearward ejection. I ended up buying one of the old GI clip-on deflectors, which solved the issue... sort of. Instead of hot brass hitting my head the spent(and very hot)brass would drop into the crook of my arm. The plastic deflectors used to be everywhere for $10 or so. I don't think I have one anymore but I'll look around.
Didn't try the coil-clipping method, damn it. My friend's old, old SP-1 ejected brass straight out of the ejection port into a pile about 3-4' to his right. Mine would drop them the same distance right over a right-handed shooter's shoulder. His rifle was a trip, as it has been shot so much that the first 4" or so of rifling was GONE. It would shoot accurately for the first mag or two, but when the barrel got hot the rounds actually would start to key-hole badly. The first AR-15 I've seen in which the rounds "tumbled going through the air" like I've heard so many ignorant stories about!!