As others have offered I suggest putting the bushing on the other side of the router tab, be sure your travel height will not run the bushing into the top of the carrier. I tried several glues and ended up using JB Weld.
The casting of the router base is fairly rough (is was not originally designed to move up and down on the fly). I sanded the entire inside of the router base and the alignment pin grove to remove all imperfections and finished with 600 grit wet/dry sandpaper. I sprayed the router body with dry graphite lube and it makes the z axis move like butter and has been durable.