Hi Al and Yves, The stock brass bushing dimensions: ID 3.15-3.20 MM, OD 5.55-5.60 MM, flange OD 8.03 MM, flange thickness 0.68 MM, bushing thickness 3.55 MM. These bushings are glued into the side frames and pressing them out can damage the side frames. The other problem is that the axle is slightly longer than stock Aristo axles and knurled to hold the bearing caps on which makes them slightly larger on OD. The axle stub OD is 3.00 MM. I had to bore the bearing holes in the side frames to 6.00 MM/0.237" to accommodate a 6.00 MM OD bearing. I don’t recall if I installed a bearing with a flange, but it cannot be thicker than 3.55 MM. I do recall filing down the knurls on the axles to be able to get the axles thru a 3.00 MM ID bearing and using a drop of crazy glue to hold the bearing caps on. I had to make jigs to hold the side frames for removal of the brass bushing, boring the holes to fit a 6.00MM OD bearing and pressing them in. I did the boring of the holes on my mini mill. I used a small arbor press to carefully install the bearings in the side frames using the jig that I made up to support the side frames. This was done to Aristo 53’ Evans box cars. The truck mount coupler shanks were cut off and Kadee body mount couplers were installed which had to be modified to swing wider.
Bob MacGregor in CT