I decided to take it all apart again and investigate further.... everything holds true until the last turn on the front bolts on the mast plate on deck
, when the plate underneath on the saloon
roof pulls up at front
which in turn offsets the post forward 25mm at the bottom.
I put in a few shims, only 3mm was required, tightened everything up again and the post sits where it should.
Now i have the solution i need to take the whole thing apart again and clean the bolts and holes of sikaflex before a final fit.....
I think the reason was that the aft bolts were screwing home , but the front ones were not and as a result were pulling up after the rest were tight?
Anyway, thanks for the wake up call rognvald.