Here is a repro wheel center. Check out the radius where the washer sits. Last year I had problems with wheels not spinning once I tightened them up on the bike. This little radius causes the washer to not sit up against the wheel center like it is supposed to.
See the light in between the two pieces. There are two ways to fix this issue, you can either cut a right angle in the center or bevel the washer.
I beveled the washer for two reasons, 1 It is easier and 2. The wheel center is depth hardened, and if I cut a relief in the center it would cause a weak spot.
Here is the finished combo ready to go. Hopefully this tip saves you some future headaches