Any companies you recomend with the stock computer? Done a bit of research on the Sublime system that looks to be ok, i just want super simple as running the 904 and want it to be neat
Honestly the only ones I know of are Hotwire Auto and Sublime.
I know Hotwire sets their harness up to poke through a hole in the firewall and hide the PCM. Generally they use a '10-'12 or so NGC controller. I know you can get a harness and PCM from them all at once and they will work with you, but I think they are 8 or so weeks out, too.
Sublime can probably do any setup too, but they are a little more on the side of a stock harness with some mods which generally means the PCM is under the hood. But they can sell a harness and PCM as a set, too. And it seems like they are more on the end with the later GPEC2 controller.