Is it NEC-compliant to place a GFCI or AFCI receptacle or deadfront device in a location not readily reachable?
Check 210.8 Ground-Fault Circuit-Interrupter Protection for Personnel.


  ...The ground-fault circuit-interrupter shall be installed in a readily accessible location. 


And 210.12 Arc-Fault Circuit-Interrupter Protection.


  ...The arc-fault circuit-interrupter shall be installed in a readily accessible location. 


Then Article 100, for the definition of readily accessible.


  Accessible, Readily  (Readily Accessible). Capable of being reached quickly for operation, renewal, or inspections without requiring those to whom ready access is requisite to climb over or remove obstacles or to resort to portable ladders, and so forth.