What did you damage?
I had no issue installing mine does it have something to do with closing the viewfinder shade first before you screw it on?
https://youtu.be/C06A8gBK7U0
it was a while back so i don't quite recall but i think it was...the exposure values and whatnot are blurry....the view of the shot is fine but the rest is blurry but readable. shots come out fine. the funny thing is if i put my glasses on and use the vf, everything is good ...maybe i'll stop wearing contacts.