Hey everyone! I’m actually working on this same effort with my detailer as well. They expressed concern about wrapping the antenna in PPF from a finished-look perspective due to the contours of the antenna.
The cleanest (albeit priciest) solution I’ve found was to order a new antenna from my dealer’s Parts Dept (my dealer won’t install non-dealer ordered parts, so that’s a pain point when I could order that thing from almost anywhere) and have it painted by the Collision group (estimated $200 for painting; TBD) to match the detailer-provided swatch of STEK DYNOblack-gloss PPF I will be using for the roof. The dealer will install the newly painted antenna and I will have an Electric Blue paperweight

. I imagine antenna install may be $painful if removing the headliner and attaching the new part becomes labor intensive, but we will see what happens. I also realize this approach may be overkill, but it’s another option not totally discussed previously.
Edit: Painting your current antenna could save costs if you are the committed type and want to skip a redundant part purchase.
Here is the part number for the antenna if needed:
GM Genuine Parts Black High Frequency Antenna
GM Part # 84746762
Current price on GM Parts site is showing $171.32 for me. Also, there’s a promo code showing 15% over $150 spend currently going thru today I believe.
GM Parts Site
FYI, I also bought the black shark fin cover from Savage (still uninstalled in box), however I can’t ease concerns that any cover could interfere with antenna functionality (this is just my non-scientific opinion). It could very well be a non-issue; YMMV. The Savage cover attaches to the actual antenna with a 3M-type strip along the bottom portion of the antenna. I wanted the cleanest no-stress approach to completing this part of the detailing work correctly the first time.
I hope this is helpful. I enjoy seeing the many different methods to achieving a nice customized look for our cars. Drive safe!