moerch armboard spec

Does anyone know the diameter of the armboard hole required to mount a Moerch tonearm? How about the Naim Aro?

20mm diameter hole, 212mm spindle to pivot distance (pretty sure on the last one)
Yes, that's correct. Good luck finding a 2o mm drill bit. I lucked out because my buddy lent me his. He happened to buy a Moerch arm a few months before me and spent a few days going to various tool suppliers before he found one that was suitable.
There is a website with the specs.