Torque wrench? OK. What are the recommended values for the aluminum manifold vs. iron?
Considering the replacement cost of the manifold I wouldn't torque anything on it more then 15-20 which is snug with a box wrench.
I would wager that more manifolds have been broken in attempting to use the cork s pieces, because you need to COMPRESS them, then anything else and I'd double or nothing that NO ONE exceeded the recommended torque when they broke.
Stay away from it. If you drop it, you can hurt your foot.