The following Engineering Change Notices are available for download:

PL-1

ECN-01,
ECN-02, 11/1965
ECN-03, 03/1966
ECN-04, 09/1966
ECN-05, 01/1967
ECN-06, 05/1967
ECN-07, 08/1967
ECN-08, 08/1969

PL-2

ECN-01, 11/8/1969
ECN-02, 5/17/1970
ECN-03, 8/15/1971
ECN-04, 3/18/1974
ECN-05, 5/10/1980
* Notes on the additional fuel tank.
* Additional notes on the landing gear manufacturing procedure.

PL-4A

ECN-01, 03/1973
ECN-02, 05/1973
ECN-03, 01/1974
ECN-04, 08/1974
ECN-05, 03/1975

PL-9 STORK

ECN-01, 09/1994
ECN-02, 08/1995
ECN-03, no date on ECN
ECN-04, 08/1995
ECN-05, 04/1997
ECN-06, 06/1999 *
ECN-07, 10/2008 *
ECN-08, 03/2009 *

* Notes: With the exception of ECNs 6 and 7, all plans purchased on the date of the ECN have all ECNs up to that date incorporated.
** Please Note: Typo on drawing # 9-10-004, zone C-8, dimension of channel is 65.9 not 69.5.