When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Gears will make a bigger difference than a driveshaft, but you can install a driveshaft by yourself. If you dont have an intake/tune yet, I would go with that first because you need a handheld tuner to recalibrate your speedometer when you change gears.