I remember buying a Fhone amp at a used car dealers as it was used as a deposit. It had a speaker box made of chip board and coated in fiberglass.
Then as it became a bit crook, i contacted Sid Grondman and he sent me a circuit diagram and I fixed it.

Then i got Sid to make me a PA, but the speaker boxes were made to fit my car. 4 12UX50's in the two boxes. Still got the speakers but the mice pissed on the transformers and nothing wrks. 6CA7's in PA and 12KT88's int he guitar amp.