Yep, I see now. Thanks for that Warren and others. Forewarned is fore-armed as they say. Warren will probably agree with me here but working on a bracket is a sod of a job because the part you want to get to, the cradles and threads - or in this case, the anti-rotation slot, are the hold-ontoable parts!!!!! When I had about 70 or so virtually corroded to scrap brackets to do I used a scrap No4T body and mounted the brackets onto the body which was mounted into a milling machine/drill press. That was the only way I could get a secure and more importantly, square hold!