How do I complete mission 12 (Hellbound)?

[CobaltNinja]

So I'm trying to progress in the story, and this mission is screwing me over big-time. Here's the general run-down.

After skipping the cutscene, I use a cardboard box and tranquilizer to sneak out of the power-plant. I don't try and interrogate anyone, I just straight up get the hell out of there.

Next I mosey my way through the 3-4 guard posts to get to the base camp, being sure to neutralize every guard so as not to put the base camp on moderate alert.

After I reach the base camp, I turn the power off and hold up the guy that goes to check it, neutralizing him. I try to be careful not to get seen by the helicopter.

Now here's where it goes downhill; after putting him out of sight, I use the box to sneak through the archway into the camp. A walker comes along, and I stop. He sees me and goes to check; after having his headlights trained on me for enough time, he spots me, and I get royally ♥♥♥♥ed over and have to restart from checkpoint.

All I really want to do is complete this mission, but how do I do that? Tips or tricks I'm missing? What is it?

(Note: I do NOT want to use the Chicken Hat or Stealth Camo.)

[!RJ_Truth]

Originally posted by lazy skunk:

Originally posted by NukeDoctor:

I'm still trying to work out a no traces myself.

you can't no traces hellbound. because you have to shoot a minigun at the final.

Yeah.... I just watched this one....

https://www.youtube.com/watch?v=7VBQ2wcKGOY

...and that's as Perfect Stealth with no weapons as you can get.

[nwo anführer]

oh yes... that was a pain for me...(i needed 3 starts for that) i killed all solders and finished the mission