Need help with C5 nitrous hookup
What I would suggest:
1. Remove Battery (8mm/12mm)
2. Remove Battery Tray (14-15mm??)
3. Loosen fuse block (2-10mm nuts; 1 near bat tray, 1 up top)
4. Loosen radiator reservoir (3-10mm nuts; 2 on top, 1-lower side)
5. Remove passenger seat, 4-15mm nuts. From there you can just flip the carpet up.
This opens up the area for nitrous line routing and easy hidden wiring.
NITROUS LINE: Route the nitrous line from inside the car along the rocker panel, up through the wiring grommet (or knock a small hole in the fiberglass next to it which is the easiest), entering near the battery tray area.

WIRING: Note, next to the fuse block is a shielded direct battery source.
I would use this for the positive side of the solenoids. Of course, you should fuse the line at around 30amps and then use a relay for the actual activation of the the solenoid. The relay can be hidden beneath the battery tray or fuse block. Ground points are noted, though in your case I would use the one
by the hood bolt down and nearest the coolant reservoir. If using a controller, can easily be hidden under the battery area. For the solenoids, I would remove the radiator hold down (4-10mm bolts), pull back the rad shield and mount the solenoids there. That allows the shortest supply lines for N/F.

Pic to give you an idea where the nuts are.



