Little bit more progress to report.
I've had the bottom end balanced by Andrews Precision while it was apart, so the crank, flywheel, clutch and damper (and oil pump drive just to be anal).
Its surprising how much material has come off to get it to balance perfectly, but i'm now told I can 'rev it any rpm you like safe in the knowledge there are no forces acting upon it'. Which is nice.
Here's the assembly as I collected it.
Close up of some of the material removed from the crank.
The damper had a chunk missing from the outer ring, the guys balancing it said you'd expect to have to remove some material from the opposite side to get it to balance, but actually this is what was required.
I collected a full set of cosworth bearings on friday too and have now set about plastigauge'ing them to set my clearances.
Nice new bearings.
Crank carefully placed in the block.
And the result after torquing the cradle down and then removing it - the plastigauge is squashed and I can measure the tolerances.
Thats the mains done, next i'll do the big ends. Once they're OK i've got all the bits I need to put the engine back together so i'll be dropping it in the car over christmas.