Or you could simply drill and use grommets to get the coax out. I have run many wires from the inside to the outside on various vehicles and NEVER pinched the coax. Actually, the coaxs aren't pinches on our 18 trucks with dual antennas at work either.
If you are gonna drill a hole mount the antenna in it an the coax winds up inside the vehicle without a grommet.
I've take a drill to the roof of a brand new car enough times that it doesn't even worry me anymore.
Friends have watched in fascination while I got out my Sawsall and walked towards a brand new pickup truck and proceeded to cut a 22x30 hole in the roof. (I haven't owned a vehicle without a sunroof since 1984 and I see no reason to stop cutting holes in my car's roof now...)
drilling a hole in the roof for an antenna is about as emotionally interesting to me as taking a piss.
BTW, the antenna I personall recommend?
a Diamond NR770HNMO.
Mine is the NR770HNMOB (the "B" means it's black)
Avoid the BIG antennae like the SG7900 (the BRASS fold-over
pivot point is weak)
In theory the big antenna getting more signal out is great, but once it snaps off it isn't gonna propagate much signal.