nagrom - i would say a deeper rim is in order, as well is higher spoke count. don't know what your A23's are spoke count wise, but I would go one step up with a deeper rim too.

jdg - if your friend has means to precisely characterize the dimensions of the hub and is good with some g-code software like autocad or solid works, then absolutely CNC that ****. If he plans on operating the machine manually, then do what you want but those are expensive hubs and you better have a lot of trust in this guy.