simple one inch atenna increased length
 

this is similar to the type of thing you would do for the bit...
you just open up the plastic cover, flip open the PCB board, and untie the knot there...
i havent seen how much improvemnt in distance yet, but im sure its only a few feet increase...but better than standard

you could also make a small hole in the roof, or near the bottom area of the windshield...that would make about a 2 inch increase from the stock....but i havent done this yet, ill do later

hope that helps