Go to cadillacfaq.com and search for a thread called Installing a JL Audio Cleansweep....I have the same system you bought in my car and this shows how to hook it up....also, there is a thread on this forum called "nerd needs help from geeks" or something like that....this explains your line convertor questions.....PM me if you have more questions after you look at those
Welcome to the fun
Welcome to the fun