On the 72 it's just the 2 screws on the the frame. Clock may just need a C battey if original - if the battery was left in and leaked you'll need to replace it. I used this one and believe I had to snip a little of the tip off the hour and minute hands to make it look right.
Handyman1425 I assume you are talking about your 72. There are four screws holding the central control panel on. Remove them and the panel will come out. The clock is battery operated so probably the battery is dead and need replacing. It does tick quite loudly when working so you may want to replace it with a digital one. Search this site to find one to use. 2 3/4" (73mm) Economy Quartz Clock Fit-Ups with Bevel Edge Bezel - Clockparts.com
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