Consider setting seam location to random and/or forcing the seam to the back of the mushroom's face. By default, slicers often place the seam near the mushroom's eyes.
Assembly
Glue in eyes and dots - hot glue or a similar thick glue works best because these parts are intentionally loose. If using superglue, apply to the outer ring of the dots - these are the only surfaces that make direct contact with the top.