Hi, new member here. Getting ready to buy a 2021 Silverado 2500 and put Four Wheel Camper on it. I'm trying to figure out some issues with cabover part of camper and the "shark fin" antenna on roof of truck cab. I understand that the shark fin is the antenna for XM radio reception. Is it also the GPS navigation system antenna, or is that located elsehwere?

 

shark fin:I think it is everything cellular...phone, gps, xm.
am/fm is still the 3 foot mast antenna