Battery ground locations

Hello all I'm new here so I apologize if this is a common question. I cannot for the life of me find any information regarding the ground locations for a 2nd generation 4 runner. From what I can see there are 3 main grounds. One short one goes to the fender. One goes underneath the vehicle to the frame. Then there's a 3rd, and this is the one I need to replace. It joins with other wires and goes under the battery area. I understand it is going to the engine block? I was unable to locate it. Can somebody look at the photo and tell me if I'm getting close? This ground cable has become very corroded over the years and I want to try to replace it before I try a new battery. The truck failed to hold a charge overnight and thats what started this whole goose chase