I’m going to be installing a Sirius plug-and-play unit, and I would like to adhere the antenna to the roof instead of relying on the magnate.

What type of adhesive should I be looking for?

 

You really won't need to. The magnet is very strong. There's a plastic "cover" that goes over the wire from the antenna to the edge of the roof that has adhesive on it. Between the cover and the magnet, mine hasn't moved in the year it's been installed. It's been through automatic car washes too

 

You can use 3M double sided tape for automotive trim. It is the same stuff car makers use on the emblems and satellite antenna. You can get it a Pep boys or any automotive paint shop.