If you're talking about the "Carnage" that's near Boulder, you're sadly mistaken my friend! :laugh3:
In short, I've heard Grant Barclay mention on several occasions that he uses Carnage to test the mods he'd done to his Durabak'd rig - If you've seen Grant's rig, you'll know this trail must be a big 'un to test his rig.......
I ran it last fall and it's a nasty little trail. There are no bypasses intended to get a vehicle through the whole trail. There are some "bypasses" to certain obstacle areas, but the bypasses are - for the most part - just a slightly easier obstacle.
My opinion of "Carnage": If you value your bumpers, lower rockers behind the rear wheels and your lower door skins - you have no business being there. Additionally, if you don't have good rocker sliders you're just asking for big damage. A rear locker is a must.
As far as lift goes, it all depends upon how much body damage you're willing to risk. A rig with 3" lift, 31's and a locker could make it through - but would get banged up and strapped frequently. Ideal set up would be 6", 33's with selectable front locker and lots of armor. I'm at 8", Detroits front and rear, 35's and 1/4" steel armor parts all over - and I still managed to smash my left rear lower rocker and bash my driver's lower door skin.
Now, if the group wanted to make a long day of it, the better equipped rigs could run Carnage and the others could drive up Left Hand Canyon (it runs parallel-ish to Carnage and meets up at the top) then they could hike down into Carnage to watch the technical stuff. Or continue further up Left Hand Canyon.
Hope this helps! Have fun with it! Wish I could join ya....