I'm looking at getting an MS version 3 within the next two weeks or so. I was on RS autosport and compiled a list of the things I'm going to need. Tell me what I'm missing that's going to be important.

MS v.3 modded for 420a
wire kit
injector plugs
coolant temp sensor
air intake sensor
relay board
wire kit for relay board
all of this is about 628 shipped

any of you guys know of a better place to buy it for possibly cheaper?
I sent them an email a few days ago but never heard back.
I know this was a commonly posted thing a while back, but a lot has changed since then and I had a hard time searching for current information.
I'm also going to pick up a new boost gauge and wide band o2, suggestions on that? I was planning on the Innovate motorsports.
Last question, what does the MS do to your emissions control. Will it trigger the Check engine as I think I'm due for an emission test this summer. My state they jst plug into the obdII.

Thanks in adance for all of your help.

Fully Built MS powered 99' GS Sport, Garrett T3/T04e 60 trim with one big ass intercooler!

Yeah, she runs...sorta!