Scorch + 1
Pretty much covers this and no, you don't have to remove the bolt. I have used these mounts on two occasions. The only thing I might add is, if at all possible, tape the face of the reciever at the contact points. This will reduce the possibilty of marring the finish on the reciever. Accuracy has never been a problem for me as most of my shots, are under 60yds. ...
Be Safe !!!