I had a gremlin removed at the Caddy dealer 3 years ago. Techs were trained specifically for trouble shooting the drop top on the Cadillac but had me covered in no time. 5 days at Chevy, 3 hours at Cadillac. Just different training means and methods.
I got lucky the Service manager had visited LCC back in the day. I found the techs loved puzzles and liked the SSR a lot. I allowed them to take the R off lot for 14 miles. I still go by there for advice and looking at the Caddy hotrods. CTS-V coupe is coming. Over 525 hp.