A retaining mechanism having a retainer member, plunger member, and an engagement indication assembly. The retainer member has a body that defines a void having a first end and a second end and extending along a length of the body. The plunger member is located at least partially in the void and has a length greater than the length of the void. The plunger member is movable a first position in which a portion of the plunger member extends beyond an end of the void, and a second position in which another portion of the plunger member extends beyond another end of the void. The engagement indication assembly includes a retainer member linkage coupled to the retainer member, a plunger member linkage coupled to the plunger member, and a flag member coupled to the plunger member linkage and the retainer member linkage.