That's good to know Simon. It seems from what I've been reading that the speakers make a huge difference (unsurprisingly)

I'm not sure what you mean about the layout missing the OT? The wires are either side of the 6V6, unless I'm misunderstanding you?

It definitely isn't the clearest layout though. From what I was reading the circuit never changed, so sometimes layouts fail to mention things like filter cap values or OT values because they are always the same as the original.

I haven't actually gone through the schematic and layout to check yet, but will work from the schematic in any case

Click image for larger version. 

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