Actually, the STS kit is the only KIT there is for the ram, sadly. You can part one together easy enough, but you just have to make sure your turbo is mapped to your driving style/intended use. The benefit of the STS kit is the pre-fab turbo oil send/return system. There are a few builds where the turbo is mounted in the engine bay, but every single one of those has required custom tuning, to the point where almost all have had to install a stand-alone computer and manually do it themselves.
When I originally started putting together a turbo system for my '07 I must have spent days trolling over all the forums and came to the conclusion that doing a turbo is a HUGE investment, in the ball park of $10K, to do it safely/properly and it's easier to get the STS kit.