just sliped a 1" copper pipe coupler over them and it fits fine, $1.00 for 2, dont c the need two close up the end like in that overpriced bushing.

looks like their epoxied in. u can weld 1 in or close up the hole by welding it drill and tap it, i would buy 1 of those small retainers they make for hanging stuff on sheet rock with no stud, they expand when the screw goes in, they also have the push in spring loaded ones.

 

First of all, I have NOTHING to do with the company. I'm the first to say they are overpriced. Having said that, they are very high quality machining. Time is spent on them. And since I shared the cost with a friend, it was just mildly overpriced, instead of greatly overpriced!
Bottom line, it is fixed, and it would seem forever, so for me it was worth it!

Brian