As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RIGHT 'T/R UNSAFE' ILLUMINATED AND WOULD NOT GO OUT. THRUST REVERSER WAS CLOSED AND LOCKED NORMALLY. SUBMITTER STATED THIS IS A KNOWN PROBLEM AND SUPPOSEDLY HAS BEEN FIXED WITH A MODIFICATION TO A DASH 3. DASH 3 WAS INSTALLED. PROBLEM GONE.