Water Leaking Around Water Pump Bolt

My most recent experience... I put my relay enclosure on the right frame rail so the swing arm of the alternator mount needed shortened 1.25 inches. That bolt had to come out. First drained the radiator.
RTV works but clean and dry is a must. Easy enough to wire brush the bolt but I had been gone a few hours altering the swing arm, etc,,, and the bolt hole was still dripping coolant. So...
I pulled a heater hose and flushed the system with clear water until all coolant was gone. Followed with compressed air, removed the belts, fired it up and let it run a couple minutes. Engine heat got everything warm and dry.