Ken B Danbury , CT January 20, 2015 Appliance: General Electric Microwave PVM1870DM3WW Ge Microwave Pvm1870dm3ww: The top vent assembly fell off our microwave. How to replace Grille Asm, Ww. I ordered the replacement grill assembly, which arrived a day later. The fix was very easy, just sliding the plastic hooks into the slots along the bottom and screwing 2 philips screws on the top. The plastic hooks on the bottom are clearly a weak point and poor design. Even the new assembly which arrived had 2 of the hooks bent slightly upward. I had to very gently bend them back down to fit into the slots, hoping I wouldn't snap one off, which is I believe what failed on our broken assembly in the first place. Do-It-Yourself Rating: Repair Time Estimate: Less than 15 minutes