so that went fairly well.
though for some weird reason s3d just kept moving the head to the same 3 spots. centre, middle left and back left.

But then I spotted a fairly serious issue with the extruder setup.
Between the extruder and the heating arrangement and the nozzle is an aluminium block. It's what you puch the bolts through to hold the mottor and extruder in place. Between the bottom of the extruder and the top of the metal block there is about a 5 mm gap.
I guess whoever drilled the block drilled the extruder mounting holes in the wrong place.

Not something you'd notice untill you load flexible filament and watch it come out sideways :-)
So that need sorting today.
Also need to start designing a top mounted filament holder.