Most Auto-Trans equipped 1st Generation W-Bodies have a large hole cut through the firewall between the driver's side strut tower and the brake master cylinder. The hole is plugged with a rubber grommet which can be easily drilled out to allow you to pass your amp wires through.



The reason for the giant hole in the firewall? Simple. It's where the clutch master cylinder is mounted on the W-Bodies that received Manual Transmissions.