It's interesting that you met someone who thinks that EC's amp was a regular JTM45.
Maybe I should expand. He's not just a "someone", for want of another way of putting it. At the time, he was a well known player around the London circuit. He was a very early Marshall adopter, I bought his block logo JTM45, which he bought with the proceeds of selling his white front JTM45. He also owned what was, very likely, the first 'burst in the UK which he bought in early '62. He's an extremely honest and methodical man, with a pin sharp memory, so I don't take what he told me lightly.
He'd seen Eric play a few times, and after a small club gig mid-week somewhere (I can't remember where he told me, but he remembered precisely), they chatted after the show. He talked to Eric principally because he was interested in his amp. His strong recollection is that the amp was an ordinary JTM45 in a 2x12 chassis with 652's. They also talked guitars, both being 'burst players, which was very rare back in the day.
So, this guy wasn't just a regular music fan. He was a working musician and guitar geek.......as he remains to this day.