What I would suggest is finding a set of studs that has the same knurl size as the current studs that you have. Or if that size isn't available make sure that you actually buy a reamer as they are less likely to wobble. I know this because I used a drill bit to bore out my front hubs to 39/64" which is the correct size for my knurl, but the bit must have wobbled. Even though I used a drill press. After 500 miles I checked my front wheels and 3 of the 10 were loose and able to be pushed out by hand.
My 2cents.
Also for what it's worth, the rear axles are hardened, and be prepared to go through at least 5 drill bits.