Definitely Carter and Definitely Shaganappi. I would try Capital as well but I have not done so as of yet.
I do not support the CMP Group (CMP, Shaw & Okotoks). I also am not a big fan of GSL. The only rule of thumb I’ve learned is to make sure the dealership you decide on actually sells new Corvettes. Even for just simple oil changes.
I will travel to Red Deer, Westaskiwin and Edmonton (Northgate) for service as well because the drive is nice. I’m actually heading to Edmonton next week to pick up some parts (best price) ... and hopefully say hi to some corvette friends there too

There are also a few decent auto shops and one I know of is ZR Auto and
@MikeysZ06 has experience with them.
Davenport is another place I am going to “entertain” once I am past warranty on my C7s.
Anything more specific ... feel free to send a PM