Sounds like your buddy has his hands full. A clutch/ladder bar car can make for a violent setup. And if it also dead-hooks that can (at times) add to the problems. You can't always use the same tuning ideas that you would for an automatic car because a clutch car doesn't benefit form a stall converters torque multiplication effect. That's why you see some clutch cars need some amount of wheel spin/rotation at the launch to work right. I'm not saying it's impossible to dead-hook a clutch car, but doing so might work better with an adjustable slider type clutch. He might just have a combo that needs to wheel stand to work (like a number of super stock cars do), and it might never be able to leave like a calmer 4-link car. But there are a few things to try because there is so many different ways to adjust a car.
If he wasn't actually dead-hooking before, and was really spinning the tire a few rotations at the launch, this could explain why the tighter extension (rebound) shock settings made the problem worse. The tighter shock setting could have slowed/calmed the initial suspension hit/smack just enough that the tire/sidewall had a fighting chance & hooked with less launch spin/rotation, and the car came up higher/faster/harder.
Just messing with the rear shock's valving probably isn't going to be enough. And since the ladder bars only have one lower hole left, that might not be much help, but if that's all you have left it's worth a try. On the other hand he might also try moving the bar to a higher hole. Yes this might sound wrong but sometimes hitting the over-worked sidewall harder could induce more launch wheel spin/rotation which can throw away enough inital "hook" to slow the front from rising as much or as fast.
He can try a taller slick which would give him more sidewall to wind-up. This could calm the car down a little as it spends more energy/time winding up the extra sidewall instead of climbing the ring gear. He can also try a different rear gear ratio to change how hard the motor's low end power hits the slicks to help make their job easier. Longer wheelie bars are another idea to look at.
Even though the front suspension travel is currently limited, that might not be enough. If it's front shock extension valving is set real loose there might not be enough lift resistance, even with limiters. Yes, limiters do control a cars front suspension travel, but not the inertia the chassis builds/stores up during the amount of travel that is allowed. At times being able to adjust the speed of the front suspension's travel with valving is more important than limiting the total amount of said travel.
Just remember if you try all of the so called "right" chassis tuning ideas with no luck, don't be afraid to try something that "theoretically" shouldn't work. Even if 10 other people say it won't work, you just never know when an off the wall idea might just be what is needed.
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