I like my old gear rattle and miss it. My 2001 has no rattle.
It is the natural result of the "lope" of the old cam, as the engine firing causes the crankshaft to accelerate and decelerate, the gear lash causes the gear teeth to rattle slightly against one another.
IMO, it should not be "fixed," but enjoyed as the sound that a no compromise, high performance car makes. It only happens at idle with the clutch engaged - spend less time at idle!
Chevy "fixed" it with the enormous "dual mass" flywheel. Dodge "fixed" it by making a "creampuff" car with a milder cam and (I think) slightly higher idle rpm.
Seriously, it can be alleviated with different gear oil (see your Viper Tech for a bulletin) and you can also have your coputer reflashed to idle about 50 rpm higher.
My personal vast preference would be that people be educated about this "problem" going in. If you want a quiet car, get a Lexus SC 430 or something else. The Viper is a take-no-prisoners performance car and I would personally prefer a little noise if it means more performance.
