I'm sorry guys, but I just don't understand why you guys feel the need to break the vacuum. The yokes come of simply by undoing the 2 clamps (which are usually SS).
I'll also add that while the glass way well be leaded, it is also coated in lead, including the outside of many CRTs. If you don't believe me take a knife and scrape that black coating and see for your selves. Just a reminder that lead is absorbed through the skin so use gloves when handling those tubes.
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