my daily radios are the vhf/uhf and aprs setup. they both run on 1/4 wave nmo antennas mounted on comet rs720-nmo hood mounts. I, too, couldn't bring myself to cut any holes...
here's a link with pics of the mounts I took a while back
I also pop a magmount on the top w/ a 5/8 wave 2m antenna when needed. I have been using this antenna as the receive only antenna on the hf radio, recently. However, as I park in a parking garage at work, I can't leave that one up, so the hood mounts have to do for now. I can't even stick a 5/8 wave on the hood mounts as it'll bang all the way through the garage.
I'm prolly going to get one of the nice dual band 2M/440 antennas and an atas-120 (or some other screw-driver type HF antenna) at some point and mount down on a bumper guard.
I will probably always carry the magmount in the back for times when I need the antenna on the roof for best coverage...
as for damage to the paint, that's a real problem. All vehicles I've used a magmount on semi-permanently have ended up with scratches. I've been using a clean shop-rag that's cut in a square just bigger than the magmount to put between the magnet and the roof. So far, this has worked well. It does get wet and need to be pulled off and cleaned, tho...you can just barely see it in the "dirty pic" on the 3rd page of my gallery thread that's linked in my signature here... you can also just barely see one of the 1/4 wave antennas/mounts there too.
Kev
PS good luck with the test, erik...you'll prolly have no trouble! 'specially since you're a full novice/techician class...I got my license right when the no-code tech rules were adopted...so I still have cw to deal with...

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