Well... Sometimes one have to admit when being an idiot....I believe to have located the issue.
When checking the pipe to the map sensor i did not check the small rubber connecting hose from inlet to the pipe. This hose was completely split...

So it very much seems that this could be the problem...
Will repport back when I have got round to start it up. Need to assemble the fuel system...
Talk about missing the obvious

Thanks Stevie for making me go back checking things already checked (sort off)

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