Also, if you're getting custom axles made most, if not all, of the axle companies will drill multiple bolt patterns on the flanges if you want. Not a bad idea to have options for the future. There's often a small charge for the extra patterns, but sometimes they don't charge, or roll the option into a package. If you have the extra patterns drilled and tapped into the flanges the unused holes can function as the access hole to get to the retaining plate nuts if needed with a ratchet extension through the hole.