Compustar 2w900fm, Chevy Colorado

Long story short was given to me as gift. My brother thought I was able to install. I have never done anything like this but prob capable. Can not afford to pay for install qouted $150-225 and no one would warranty because it was purchased on ebay. Also, ebay dealer will not refund r/s. I have search the forums for info and have found some; however, I still have questions. Hope someone can help. I bought a DEI 555L-W interface.

1-Do I disconnect battery while I make connections?

2-Do I use door triggers if this unit is only remote start?

3-I can ignore the wire for 2nd starter, 2nd acc, or ing?

4-Status wire goes to 55l-w?

5-For unlock do both the unlock output and the 2nd pulse unlock output get connected to the same wire?

6-Rearm wire is stated to be connected to dome light cicuit but the polarity needs to be changed. According to Directwire wiring info the dome supervision is the same (-) as the rearm pulse. Is this the right connection?

7-Disarm wire where does this go?

Sorry for prob asking simple questions but I could not find answers thur seach and compustar wont help w/tech because I am not a dealer.

Thanks Scott

1 No   2 No    3 No   4 Yes   5 No second unlock is if you are doing drivers door priority.  6 There is NO way to control factory security, without using the factory trasmitter! 7 See # 6

Good Luck