I have an 89 5.0, and cannot get my alternator to power vehicle or charge battery. I replaced the battery, alternator, serp. belt, battery terminals, alternator plugs... Car starts with charged battery of course, but dies when I unhook, positive cable. Someone suggested the couplers I used on the wires may not be letting enough volts through.. Going to solder the wired and shrink tube them tomorrow but does anyone have any more alternatives just in case this next step doesn't help? I've tested what eletrical components I can think of but I'm no mechanic so I need HELP!! Thanks!