A mounting assembly for attaching the drive system and stand to a ring in a medicine gantry is disclosed. The mounting assembly includes at least one mounting bar (e.g., two mounting bars), at least one mounting plate and at least one adjuster (e.g., a screw). The mounting bar is securable to a portion of the ring. The mounting bar includes a base and at least one transverse face. At least a portion of the base is substantially parallel to a surface of a portion of the ring and at least a portion of the transverse face is substantially perpendicular to the surface of the portion of the ring. The mounting plate is secured to the drive system and is securable to the transverse face of the mounting bar. Movement of the adjuster moves the drive assembly relative to the mounting bar when the mounting plate is adjacent the transverse face of the mounting bar.