I have the same problem with my 04 Sierra, and tried several things.
I have a permanent NMO on the roof, I pulled down the rear dome light for access, used a larsen 3/4 drill bit, which stops you from drilling into the liner. The headliner can be pulled down on the sides with your fingers just enough to fish the cable. I rarely can use this mount though, as any antenna there would hit my garage roof and parking structure roof at work.
I tried the
Pro-Fit International front fender mount, but was
very disappointed to find the designers never took into account the natural slope of the front fender, therefore the antenna and bracket is not vertical and sat at a funny angle.
I have been using a Radio Shack glass mount on the rear window the most, which works OK, but isn't stellar.
Recently, I just installed a Roll-N-Lock tonneau cover, so I put an NMO L-bracket on the side of that, will give that a try and post pic when it's done.
Also, something to watch for, when you pick your antenna if it's up front. Something that will drive you or your dog nuts. I had a
Maxrad BMAX scanner antenna and it
whistled like crazy at freeway speeds. I thought my windshield was leaking at first, and even took it to the dealer. Found out later it was the dang antenna the whole time.