Not sure about the M90, but there are other benefits to removing the whole thing. It gives you a chance to clean things up, keeps you from getting SC oil all over the car, and really does make it alot easier. It'* not that big of an undertaking. The hardest part is coming up with all the parts. In your case, it will be a TB gasket, SC outlet gasket, 2 coolant seals (o-rings), and an O-ring kit for your injectors. It'* a good time to do all this. Wanna get by easy? Don't pull the TB. I'd suggest pulling it for a good cleaning anyway.
I bet I could pull the whole thing and put it back together in the same time as what you're proposing.