1992 Cadillac Deville push button starter

Electrical problem
1992 Cadillac Deville 6 cyl Front Wheel Drive Automatic

I have a 92 deville that won't start, i've replaced the battery, starter, and ignition starter switch. When I turn the key all the way I get nothing, though if I cross terminals on the starter she starts right up. I was told it could be the nuetral safety switch or the security system both are costly. So I was wondering if I install a simple push button my problem is solved. My question is this, would there be a problem if I run some wire directly from the battery to the button with a 30amp fuse in-line in between then from button to starter solenoid? And will it work?