The Third Courier final mission walkthrough (Apple IIGS - Accolade)

In the last two missions, I got two of the three items containing the defense plans, but they were stolen. I need to find the third courier quickly to make sure the plans won't fall in the wrong hands. The Third Courier (
was a graphics adventure game published by Accolade in 1989 for the Apple ][. Credits: Cover art and disk image - www.whatisthe2gs.apple2.org.za Walkthrough by Michalis "Darter" Marolachakis