You can have as many opinions as you like but these will not help. You need to know whether the black labelled wires are intended to be connected together or they are start (or end). I would guess they are the start.
One way to find out would be to put the mains into the 250V output winding and measure the voltage on the series connected primary. If you get over 200V you have the two right connections. The primary should then be connected to the mains plug with the fuse and switch in series. There are are arguments as to whether they should be in the line or neutral, I would put both in the line (brown wire).
If you are not too far away from Whatstandwell, I could soon sort it for you.
Hi Duke, I am in London and if you are serious that you would help me with the amp I am heading that way on the 3rd of January would you mind if I took 1 hour of your time for you to test the transformer and show me the proper method of wiring it up, I would be happy to pay for your time to show my appreciation, please let me know, I would be so grateful but I also understand if you were not serious or that you don't have the time.
Thanks Ian