I don't know about good dealerships, but the shop to take your car is without a dobut KAB Customs.
You can see the results of my car. I've gone from one generic turbo kit to one developed and installed by them. Andres has had to do some crazy jobs on it and I'm extremely satisfied with the whole experience.
Lots of attention to detail, doing the job right the first time and great communication. No skeletons in the closet, no hidden agendas, just plain great quality work and a genuinely great guy to boot.
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KAB-FRS