No start!

[John Mason]

Have you tried disconnecting the fuel pipe to the carb and plugging the end to stop leaks then fit a small say 1/2 pint of petrol temporary take to the carb and see if it will run for longer. If this works you know it’s a fuel problem but further back down the line from the carb. If it is no better at least you know the pump is ok. You say you get a good spark from the plugs so it appears the ignition is ok. That only leaves fuel and if you have done the test I have already suggested the carb OR a mechanical problem but you seem convinced compression is there which suggest valves and rings are ok. My bet is it’s a fuel problem not enough or too much. You say your plugs are wet so that’s makes me think too much.
If I was you I would start afresh and re check everything I have done we are all prone to sometimes missing the obvious.

John Mason.