Any chance of a coolant seal break-in?
On my fifth start-up post rebuild, but first time allowing the engine to get hot enough for the fan to engage, I ended up getting a few drops of coolant out of the weep hole. The oil/water pump portion of the rebuild went smoothly and I used the updated impeller, seals and stuff. The shaft of the impeller drive gear had signs of discoloration, but was in no way worn or pitted. If it was a low-fairingless K, I'd say screw it and see how bad it gets.
Thoughts?