These HGUC kits are designed really well.  There's a nice amount of detail, a visible effort to conceal panel lines, and better posability.  The kit was not altered and was produced OOB.  I wanted to focus and weathering the kit.  I had experiemented with salt and detergent attacks that produce both texture and color differentiations.  Each has its place.  For this one I used the salt attack.  It didn't work as planned but I do like the results.  I applied this method where I felt the MS would experience extreme heat from its burners, thus affecting the nearby paint and metal.  I attempted some water staining all over the model, but is so faint that pictures don't really demonstrate it well, except on the tanks.  The rust was from an small set of Floquil (I think) acrylic weathering set.