That is not the way to do it. They don't make a direct starter button that would take that size of wire and carry that many amps. If you don't want to actually find out what is wrong with it. Just buy a start button and hook power to it from run power and then to the start relay. It's set up so you don't melt wires or start a fire. If you want to fix it check for power out of the ignition switch in the start position, it then goes through the neutral/clutch safety switch depending on which transmission you have. Then through the starter relay and then to the starter solenoid which is part of the starter. This is around a 14 gauge wire. My recommendation is to get some wiring schematics and trace the problem. Find a friend who understands electrical work.