2000 mustang 3.8l v6 no power

I have a 2000 3.8l mustang convertible w/ automatic transmission. The car had been sitting a while and had some other issues I fixed where someone installed an aftermarket edi remote start after it caused issues with the alarm going off as I tried to jump the car off and it didn’t have power.(this is no longer the issue ) As I removed the system I found a wire to the ignition switch was cut being the white/pink. I got a push button and connected this the end going back to the car to one end of my push button and the other wire i connected to the gray/yellow wire with out cutting it like I was told to do to bypass it. I got the car started and I didn’t want to shut it off so the battery could charge from being completely dead. During that time one of the wires going in the push button arched and the car shut off now I have no dash lights when I turn the key and its like it lost all life I checked all fuses and replaced the blown ones and bought a new starter relay. None of that worked. What else can I do to check and see if it hit a ground or where it would be bad next? Please no rude responses.