GMC Repair: Dont know what to do, obd 2, electrical diagnosis

Question
HEllo i hope you can help me out       i own a 1996 Gmc Top kick  , i just recently replaced the altenator, i discounected the negative terminal on the battery before demounting the old altenator, and then i charged the battery, after the battery had finished charging i hooked the new altenator up and the negative terminal on the battery.   I tried to start it and the truck just clicked and the starter kicked on it also showed i had a no battery charge on my gauge, so i hooked the battery charger up to the battery and as soon as i turn the charger on    no matter what setting wether it be engine start or just trickle  it kicks the starter on      im really at standstill with this   i need this truck for deliveries   and if i could get your solution that would be fantastic          thankyou and have a good day

Answer
this is a touch system. I will need as much information as possible. When you connect the charger (no matter what setting) are you able to turn the starter over? Does the starter kick over by itself, with the key in the off position, when you hook up the charger to it? Check your positive and negative cables for any little thing. If you find anything, you have three choices.

1. Tape the bad spot with electric tape. Use as much as necessary.

2. Disconnect the cable and repair with two "layers" of shrink hose.

3. Replace the cable.

Does the truck start when you try to jump it? Take the cables off and try to jump it that way, if need be. The only place I know of that will perform a free electrical diagnosis is Wal-Mart.

Do this and email me: marvin.saunders69@yahoo.com

Make sure you put year/make/model in the subject line. Try to also take by autozone to OBD-2 scan for free of charge. The first thing I would do is scan the codes. Any reputable mechanic should do this.