There should be a resister originally mounted on the backside of the instrument panel, This would be located up by the voltage gauge backside. This where the key switch wires are connected. There are 3 terminals with 2 on top and 1 lower. Put 1 key wire on the top left terminal and the other on the lower terminal. Check for continuety on those 2 post with key turned on. If no continuety, replace thst resisterl. This is one of the easiest place to start. I would recommend getting a shop manual ITF04. These shop manuals have all of the part numbers with a great blowup of all the parts on the 8,2, and 9n's. Wiring diagrams are in there as well. I got mine from Tractoropolis.com. and they are around $36.00 plus shipping.