60 AMP fuses?
At 12.5 volts thats over 1200 watts so it probably can't just be eliminated.
If they were 10 or 15 AMP I'd say maybe.

The best way to diagnose this is with a DC current clamp. Just find which wire at the fuse panel(s) is drawing a ton of current when the car is off.

I see what you're doing with the "spark test" but this may be misleading.