Open the file into Photoshop (or similar photo/image editing package) and cut out/edit the various parts into equal parts.
N.B.: Top and side views are recommended to remain the same height and width, this will allow correct scale. Also keep the front and back views the same width as the top/side views and the front back need to be the same width also. Create Poly Planes for each and ensure these are scaled to the same size and unit as the images.
There's a free tute on SM on Image Planes, grab it and have a gander.
Chris (formerly R@nSiD)
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When the power of love overcomes the love of power the world will truely know peace - Jimmy Hendrix
Winner SM VFX Challenge 1
3rd Place SM SteamPunk Challenge (May 2007)