Yes, the VW dealership from which I purchased both of my B5.5's installed my bost gauge and a-pillar column pod. Did I mention that they also flashed my ECU with GIAC software? And installed the 710N DV?
They also sell/install/service H&R and Eibach suspension components. And some limited exhaust upgrades (not so much for Passats, but Jetta and GTI). They do wheel/tire packages, too. And brake upgrades.
Honestly, I haven't been there in a while (I moved), but they had a display case with brake calipers and pads, short shifters, pedal sets, DVs, etc. and they offered all of them with on-site installation and service.
There's a very good reason that I really like this dealership and wouldn't hesitate to do business there again.