I'm confused by the contradictory advice on the above subject. Some reviews say the part screws on, others say it is push fit. I've tried both without success (having remembered to prevent the spindle from rotating). The situation may be complicated in my case by the fact that the original hub adaptor was shredded, the bolt now has less than a centimeter of useable thread showing, the rest of the bolt is black (I presume this is melted plastic, whatever it is I've been unable to remove it with either wire brush or screwdriver). How should I proceed?