Many thanks for that, I will return to the drawing board for the moment in that case and see what we can do, I think it would have to be the full stack as there is a fair amount of down force on this assembly,

Thank you very much - it's easy when someone else knows how! (slightly ashamed that-that solution evaded me)

That will also give me many more options for where to get it all done as well, that does make it 10 080 holes and 512 boards (wow), that is going to take a lot of sorting! Phil