UV spread

I want to use a single image as the texture to go across a grid of 6 specific faces which make up a small portion of a larger grid. I am able to do this already, but I wonder if there is a quicker way. My current method is too laborious to carry out accross the entire grid. I begin by going into UV face select mode. I shift-right-click the 6 desired faces (2 across, 3 up). Then in the UV/Image editor window, i use image>open to get the image I want to use. This appears in a square box, with a dotted line around the outside, indicating the edges of the faces I selected. If I render now, then all 6 faces will contain the entire image, creating a tiling effect. What I want is for the image to appear spread out across all 6 faces. In the image window, if i hit Ekey, it performs LSCM unwrap (which stands for…?) then all 6 selected faces appear as a grid on top of the image, but they are wide rectangles, 2 across/3up which don’t even go up to the halfway mark of the image. I just want to expand them now to evenly cover the entire image. Are there any shortcuts for this? Right now, I am selecting all vertices, then scaling until they fit. Using the opton UV>Layout clipped to image size makes it easier to fit them, if I MMB-click and scale in the vertical direction. But I have to have the grid perfectly centred before scaling, or else I can’t use the full image.
Any help would be greatly appreciated.

LSCM stands for, of all things, Least-Squares Conformal Mapping, and it is a technique for mapping (“wrapping”) a flat image onto, particularly, an intricate surface like a face with a minimum of distortion.

When you are unwrapping an object, it helps to define “seams” where the mesh can be “cut” so that, if you opened it at those seams you could lay it flat and produce an area with no “holes” in it. For example you can unwrap a cube: see the latter part of http://download.blender.org/documentation/htmlI/x5612.html.

Then you can put a single image around the entire cube.