@N0isemaker The old Cleveland model cornets, not the superiors or 600 series, have 3 slot guides because the valves use the same guides as the other hn white/king models like the master. Other horns from them with the same valve block style have the 3 point. The valves themselves dont interchange though, because of the different wrap and offset first valve slide. There is an old silver cleveland cornet on ebay now, but maybe wait a bit for a trashed one to come up, thats what I had to do when my guides were too worn out. You can try making a guide, but I tried to do the same thing and had trouble trying to recreate the pin that goes through the wider slot of the 3 slots. Maybe a different tech will be able to do it, I know I couldn't.
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