[s-cars] Boost gauge for cluster installation

[Mark Farrell]

I'm not an A-pillar fan myself, but I agree with Hap that the boost gauge needs to be easily visible. 

While having my newly RS2ed S6 tuned by Mihnea several weeks ago, my wastegate frequency valve failed, instantly sending the boost to 40 psi. The car was immediately switched off and evaluated. No problems other than the failed WGFV were found, and the Samco's were still nice and tight. The valve was replaced, and the day continued to be fun. I shudder to think of the consequences of this happening while driving down the road unaware of a malfunction. 

Mark