I have 2002 tl I was told the best place to mount a external Xm atenna (Magnetic mount)is as close to the stock radio antenna as possible???? Is the antenna on the front windshield or back ? Thanks in advance!!!!!

 

I would try and cover the magnetic portion with some 3M double sided adhesive. I have used magnetic "clamps" before and always ended up with nicks and scratches. Just a thought. Cheers!