Replaced the problematic battery terminals and installed radio aux input.

Here's some pics.

 

How did you do the radio aux input? I have the standard radio in mine.

 

Got some idea from this site http://www.kawal.net/auxinput.htm, followed the alternative 2 route and bought the same switched jack, cut and connected the wires from the XM module. When i want to listen to the iphone, i just plug the 1/8mm jack and select XM from the radio. If you subscribed (i'm not) and want to listen to XM just unplug the 1/8mm jack and it will automatically switch to XM input.

 

very nice,solid work!