The volt meter I have on my 1980 Sisu is no longer working and I think I need to replace it, unless someone can tell me it can be fixed somehow. If it matters, the engine is a Perkins 354L 115hp. Is this a job of simply disconnecting and reconnecting wires? I don't have a clue of what it is I need, I am electrically brain dead! Any help would be greatly appreciated. The volt meter is on the upper left in the photo. Thanks!