Hi Gio,
Waow incredible Porsche multi-projects !!
I love it !
I also recently decided to convert one of my 911 Turbo into the wonderfull SC RS (what a sound !!

) Group B.
It seems that you miss (or still haven't done it) that the rear wing doesn't only need to be corrected in its wight and edges shape but also has to get his "inside space" reduced. I mean that the rear edge of it is design to receive the intercooler whereas the SC RS is an atmo engine and rear wing isn't enlarge to the rear to get the intercooler.
As inside space isn't as large as the turbo one wing then appears (and is) longer from the edge of the inside space. Did you notice that ? If yes how do you intend to rebuild it ?
because that is where I'm stopped now with this project (except that I can't find time now to go on on it but it's another story

)
I have some pictures of the real car to show what I mean if it is not clear enough...
(unfortunately none of my current project, but may be able to take some this week-end)
We also have to pay attention not to look too much to the street SC RS for inspiration because it also have some minor differences with the racing one.
(bumper lips, etc...)
Do you plan to build and detail the engines ?
(appears to be a sod question knowing your talent to, but humm...

)