Starter motor query

[Eeffinger at conestogac.on.ca (Edward Effinger)]

My '81S had its 2nd tow job last night.   My daughter said the car was making
funny noises while trying to start it and ran the battery down trying repeated 
starts.
 
It appears the starter motor bolts were loose, the bottom one is missing and
the top one is finger loose with the starter motor rocking loosely.
 
That ever happen to anybody or was someone trying to steal it?
 
Also, the positive wire feeding the solenoid broke off trying to loosen the nut.
The entire post is rotating in the solenoid and visegrips wouldn't hold the
post to remove the nut.
 
Does anyone know if the loose post means the starter is toast?
The solenoid appears to have the ground welded on to the case of the 
starter motor.
 
Thanks 
Ed '81S