just to update.....as Nev and Robert have conformed the holes in the original sprockets are 1/4" give or take a few thou. The original bolts are 1/4" and are supposed to be a good fit in the sprocket. The replacement sprockets that have 0.280 (9/32) holes will, in my opinion, eventually cause looseness of the 1/4" mounting bolts and this can (as Nev says) eventually damage the threads in the hub.
Moving the sprocket anticlockwise, to take up the slack before tightening, will not work as under deceleration the forces are in the opposite direction so there is still the chance of them working loose.
I have solved my issue as Clay at Acme Stainless is making me up some 9/32" shouldered, 1/4" thread bolts to fit the oversize holes. The length also needs altering as the flange on the new sprockets is about 1mm wider then the original. I have sent him my new sprocket so that the supplied bolts will be spot on.
I have also sent him the spring for the rigid front brake rod, as at present he does not supply the spring with his stainless brake rod assembly. Hopefully he is going to get some stainless springs made up.
He is also looking at making some of the locking tabs for the rear sprocket bolts ( viewtopic.php?f=4&t=8063
). I don't have one to send him but it would be great if someone who has an original could stick it in an envelope and post it to him.