Spring Guide Remix

I added a wall in the center of the guide to provide a more sure path for the bed machine screws. Helps to make sure that everything is properly stacked.

I also noticed that the ones that I had on top of the spring (touching the bed) were heated and shaped by the bed, causing deformation (see image of the black spring guide). I fixed this by setting the metal washer on top of the spring guide (see images) and then raising the z-axis stop switch to the upper set of holes in order to combat the added z-height of the spring guides and washer.