[Antennas] AM Broadcast RX Antenna?

[KD7JYK DM09]

The station my wife wants to hear is about 1,000 miles out.

We did notice an improvement when holding the 102" whip against the factory 
antenna, greater signal strength and better signal to noise ratio, I thought 
we could do even better if it was matched to the primary frequency she 
listens to during her morning and evening commute.  She doesn't listen to 
local FM at all, so it's either 660 AM or the satellite radio.

I have a close-body CB mount to modify to match the contour of the truck bed 
and some 1/4" aluminum to make a secondary mount about a foot above that to 
really stabilize things.  On the back side, inside the fender, I can add a 
matching network, then either T into the existing co-ax or remove the 
factory antenna entirely and use just the 102" whip.  We're in a fringe area 
so the longer antenna would no doubt help with reception in general, but the 
primary concern is the DX AM station.

Kurt