mirror question..........
 

I have a set of mirrors that I was told were for an '05 f-250.They are powered,with marker light,turn signals,and heat. I want to install them on my 2000 f-250 that has only the power mirror feature.
I thought it would fairly easy to do,with some wiring and soldering the "new" stuff should be fairly easy. I have done enough searching to be able to identify all of the wires for the lights,signals,and heat.
However,the newer mirrors have 4 wires for the movement, and my existing ones have only three.
Can anyone tell me if it is possible to install these on my truck and make them operate properly?
Thanks in advance for any help with this.