1996 Ranger alarm install w/ factory alar

Hey,

I recieved my alpine sec-150r today and immediately had some questions.  I would like to integrate this alarm (its impact and motion sensors) with the factory passive alarm (locking, starter interrupt, dome light control).  From the wiring charts here, it doesn't seem as though there is a factory arm/disarm input for the alpine unit to connect to.  Can I just connect it to the factory lock/unlock circuits?  If this is possible, would I want to install the alpine unit connecting to the GEM (dash) or the factory alarm box (extra cab)?  My last total newb question is where is an acceptable location to pull the constant power source? Interior fuse box?  Thank you very much for any help you can offer me!

-haole

After looking at more detailed wiring diagrams of my truck, it seems as though I could essentially cut out my old factory unit and use all the corresponding connections on the alpine unit.  The only problem I think of is the amperages not being enough (200 mA).  Any suggestions?

-haole