Take the fan belt off and try to crank the engine over. Since the water pump was the last thing you installed, how about checking to see if it managed to lock itself up during installation. Hot cables can also be caused by the starter trying to turn an engine that's almost locked up, either with tight bearings or a belt driven accessory that doesn't want to turn. Look for the simple stuff first before you take a stroll "around Robin Hood's Barn" looking for something complicated!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!