TheOtherEric said:And another "gotcha" is to make sure your pre-drilled neck holes are deep enough for the screws you'll use, since you may end up with screws that go a bit deeper into the neck.
I never checked this after using countless necks on Warmoth or Fender bodies.
Yet I once ended up re-using the neck plate+screws from a Fender American Strat and I split the heel of the neck. Either the Fender screws on that specific guitar were longer than usual or Warmoth didn't drill the neck screws deep enough; it seems to be the former.
Luckily wood can be glued easily for a seamless repair but still not what you really want to do on an all ebony neck...