Very good idea! If I were to use a mag-mount antenna, this would the route I'd go. All of my antennas are permanently mounted though.A couple of years back, I had a Mustang convertible and ran a dual band Larsen mag mount with the large rectangular base. Before I stuck the mag mount on the trunk, I took a 4" square of clear contact paper and stuck it directly to the clean car surface. I left the base of the mag mount alone.
When I traded off the car 4 years later, I was able to simply remove the plastic sheet and all the scratches came off with it.
During that 4 years, I never had the mag mount blow over or off the trunk.
This is the way to go. If you ever want to sell the car you can have a piece of metal welded back into the hole and touched up. If it is done right you will never even know that there was a hole in the roof.You can drill a hole and mount an NMO..... No worries about damaged paint.
This has been tried by people I know. Not only can moisture collect, but also grime and grit. The product is too loose, and does not adhere as tightly as the above ideas involving contact-film or bumper-stickers. The result was a clearly marked circle with a lot of scratches where each antenna had been. The loose-ness of the plastic lets the antenna move ever-so-slightly which then causes the road-grit to scratch into the paint deeper and deeper.How about some Saran Wrap if it's just temporary?
Very true. And, even on just a long road trip, depending on the weather, it might be a good idea to use a dry towel to clean the antenna base and car surface when stopping for fuel or food.Remember that a mag mount is designed as a temporary solution, not something that be used for weeks on end.