Without tearing up the heavy duty aluminium foil screening stuck to the sides. Just what you don't need rattling around in the amp. The solution I use is a sash-cramp (USA term ?) used in the reverse sense across the back of the casing to open the gap a bit and a sheet of celluloid draped over each side , removed afterwards. Preceeded by cutting off jagged corners to the chassis, for personal safety reasons if niothing else. Is there a technique that does not force the wood casing. ?
-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on
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