Becks, Stuttgart Southwest, & Patrick Motorsports have all done tremendous work on my various Porsches over the years. I've heard great things about Zuffenhousen but have not tried them yet. Plenty of other great independent shops in town too plus authorized dealers in Scottsdale & Chandler.
You should also come to Scottsdale Motorsports Gathering (aka Cars & Coffee) the first Saturday of the month. Info at Scuderia Southwest website
https://www.scuderiasouthwest.com/smg/
And consider going the local chapter of Porsche Club of America az.pca.org