I agree with "Rickys2", there being one too many screws in this gun.
Tremendous force can be generated,with a foreign object, that close to the fulcrum point.
I think it happened after final assembly.
Saddest words you'll ever hear ... "I have these old guns that were my dads and I have no interest in them"
Teach a kid to shoot and to carry on the tradition of safe, ethical use of firearms...
That Trigger Guard Plate is jacked up. Regardless of how it was processed, it should have NEVER been accepted by Final Inspection. Still saddens me....
thats a new one for me...never seen one crack there before.
a replacement lower tang would fix it, assuming nothing else
internally is wrong.
best of luck.
Savage 99 fan