47-21-11 REPUBLIC: (Was Mandatory Note 1 of AD-769-2.) Applies to Model RC-3 Aircraft Serial Numbers 5 to 174, Inclusive.
Compliance required prior to July 1, 1947.
In order to prevent short circuiting of terminal studs on the firewall, remove each stud, enlarge the hole (0.316 drill) and insert a bushing (P/N 17F82080-1).
(Republic Seabee Service Bulletin No. 1, dated December 18, 1946, covers this same subject.)