I'm pretty sure the drive shaft spins anytime your wheels are spinning. So whether it's in neutral or not it's doesn't make a difference, so I'd likely look elsewhere. I might be wrong though (not a mechanic just learn from personal experience with my stang), sorry I can't give you more advice but for the sake that no one is apparently on these forums anymore, had to give you some input.
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No engine/performance mods (yet). Mach 460 sound system, 2 12" alpine subwoofers in a custom box w/ 1800watt kenwood amplifier. Smoked halo headlights, smoked sequential taillights, black bullitt staggered rims, racing stripes, and plastidipped spoiler. Future exterior mods - Chin spoiler, black fuel door, and demon fender flares (plastidipped).