Looking for witness

Arrived at MCRD Parris Island 07/12/1971.  Assigned to 3rd Battalion, Platoon 365.  Don't remember which company.  On first day of the two week maintenance detail, I ran into an air conditioning unit sticking out of the maintenance shed while trying to jump over the first bench in a row of about five benches.  I was knocked out, dislocated my left shoulder and suffered a light concussion.  I was taken to the medical unit, my left arm put into a body sling and was put on no duty for the next two weeks.  I am looking for any one who remembers this incident.