I am looking at installing my new headunit, an alpine cda-105, which i just bought last may, will it work with the dash controls or will i need to use the mod? Also where are the holes in the firewall to get the amp wire to the battery?

 

You need a DCI to retain the dash controls.

Modifry's wired DCI compatibility page:
http://www.modifry.com/products/dci/...patibility.htm