Porcupine has maybe three spots that might make your butt cheek tighten up. I lead this trail often.
The first half is on a road on a steep hillside. I would not really call it a shelf road.
Your FJC I much wider than a FJ40. It will be very stable unless you have a lot of weight up on a roof rack like a RTT.
I would not worry too much about it. Line your self up behind another FJC and you can see what it does on everything in front of you. I generally try to set my vehicles up like that with a more experienced driver in front of a less.
Speski OffRoad LTD, Cargo Solutions for Toyota 4x4's http://www.SpeskiOffRoad.com
"80 series, with a fridge"
1976 FJ40, Project with little progress.
2004 Starcraft 10RT