So I decided I wanted to do this, so I go in to engine bay and noticed I have two pumps, one is plugged up with two wires going in the wire loom. Assuming its the rear washer, can i tap the wires in the dash with a button to use it as my ic sprayer? and where are they at?
Thanks
(I have a sedan by the way)

I don't see why not.

Search. There are a few write ups that go over specifically what you want to do.