Keith tuners fitting in 10 mm holes

I've got some Keith tuners and will be putting them in a 1990 Stelling.  The shafts of the Keiths are 3/8" and I understand the holes in the Stelling are 10 mm.  I've read different things on the hangout re: doing this.  Some talk about these two measurements being close enough to be interchangeable.  Others talk about needing to use a little shim of brass around the tuners to fit in the slightly bigger holes.

I'd appreciate input on these two trains of thought.  I like the idea that it will work without any treatment, like shims, but I do want to do it the right way.

thanks,

Scott

and fit into the 10mm holes in my Gold Star with a little shim of metal around them.  Most planetaries use either a 3/8" or 10mm hole. These measurements are close enough to be interchangeable (10mm is a hair larger).