What size and what instrument, bass or guitar? Hipshot and Warmoth both have the PDFs with the schematics. The only problem is there may be a metric to American conversion, depending on which one you're looking at. If it's bass, Warmoth only does two reams. If it's guitar, they'll do just about any size ream you want. If you don't know, just get the smallest size Warmoth offers, get the tuners, and ream them out to the bigger size.