Have you cosidered a tranny blanket? The one you pictured is probably the smallest hard shell cover you can find. But if the trannies already in the car it will have to come out to install. These blankets can probably be snaked in with the tranny in the car, and its SFI approved also, and 1/2 the cost.



http://www.jegs.com/p/Stroud/747265/10002/-1/11877