Added 75 f250 with 390 auto to my dentside collection. There's a new alternator, solenoid, interstate battery and belts. It's charging at max output, the indicator gauge is pegged all the way to the right at full charge. The lights are brand new bright even though their old. Put in nearly dead 850 amp battery, charged it in 15 minutes to the point that it spins the motor like the plugs are out. I checked the part # and it's correct for the year make and model. Worried that I'm going to over charge battery, I have 1 more dead battery left to put in it. HELP