does this sound like anelectrical short?

[cobra196]

so i just put my rebuilt motor back in the car. when i turn the key to start position with a battery thats fully charged i get a click and spark on the positive battery terminal and everything goes off in an instant lights dash dinging noise. ill take the key out wait about 30 sec to a min and every things back to normal again. so i took that battery out put it back in to the car it came from and works fine in there. then took another battery from a car, motor was cranking had fuel and spark no attempt to kick though. finally the battery just started to die i took it out put it on the smart charger. once it was fully charged and in the car same thing happens click same time it sparks everything goes out. i checked grounds and i have the block grounded. im out of ideas

 

[STAMPEDE3]

Click and spark is a bad connection.