93 explorer 4x4 problems with alarm

this is my first alarm/remote start/keyless entry install.  I have a 93 eddie bauer explorer 4x4.  I got a copy of the wiring diagram and followed it for installing all the wires.  It did not have the color/location of the dome light wires and I am having trouble locating them.  The alarm instructions also say that I need to hook the purple wire to the generator (alternator??) instead of the tach for the remote start to work...  what wire would I use on the alternator?  Also, the door locks are hooked up and work, but not properly..  you can hear the locks motor making the usual noise, but it doesn't always lock/unlock all the way  (the knobs dont move or dont move too far)  any ideas on why that is?   they work fine from the cars switch just not the remote.  The previous owner had a clifford hooked up and I think I disassembled at least most of it.  Any help would be appreciated.

thanks,

john