Battery draining fast

New alternator and regulator cleaned up wires after reading thru similar problems and not really knowing what or where the fusible link is I'm guessing its the little wire that jumps the wire harness to the distribution just to the left . Well I found a heavier gauge wire that's been spliced with a blue butt connector . I need to find a fusible link or make one does anyone know what amp this link is ? I started grounding the alternator and regulator and rain started coming down . Hopfully it stops so I can get this thing figured out.