Kellogg Switchboard Co Amplifier - Dukane?

[newanatolia]

Trying to find info on this one that I picked up recently. Kellogg Switchboard was a telephone company going way back to 1890's I don't know if they manufactured this or just branded it. Could be dukane...? This amp looks to be about 1959 from date codes inside. 600 ohm input with a dukane 8 pin 3A65 input transformer. 12AT7WA preamp, 5u4GB rectifier and two 5881 outputs. Can take 6L6WGB's. It's a small package but Heavy! 30 watt output. Good size transformers.
Thinking about a guitar amp conversion. sorry for poor photos. First post, trying to get the hang of things...
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[KentTeffeteller]

Kellogg was then part of ITT, who owned Sylvania then. I suspect this was a telecom related AF amplifier.