Okay to use 1/4" aluminum spacers and steel screws with TPS80W PSU?

Is it okay to use aluminum spacers and steel screws to support the TPS80W power supply? I’m planning to elevate it 1/4in. above the back of a plexiglass case. I just wanted to check whether there’s any danger of electrical interference and whether the space behind the PSU is sufficient. I checked the manual but didn’t see anything about spacer size or material.