Combining Texture Packs

So, i found this mod (Extra Doors@ http://www.minecraftforum.net/topic/174 ... rge5000dl/) that also has a LB Photorealism Texture Pack for the doors themselves. Problem is, i dunno how to merge the LB Photorealism Pack with the Doors Textures. (the Doors Textures are for the doors ONLY! they dont have the rest of the textures.)

How can i, in the easiest way possible, add the Door textures from the one pack to the LB Photo pack so that everything meshes? thanks!