First off if you use FA2sp version this script is available, but it is not a option for default FA2 so you have to do it manually like this..
Make any script named "Whatever" in FA2 editor
0=Move to waypoint (near structure) in this example I used waypoint 10
1=Anything (can be attack) I used attack
Open the map in NotePad++ or just normal notepad or any text editor
Search for "Name=Whatever"
[01000000]
0=3,10
1=0,0
Name=Whatever
Replace 1=0,0 with one of the following
60,0 = Enter Grinder
61,0 = Occupy Tank Bunker
62,0 = Enter Bio Reactor
63,0 = Occupy Battle Bunker
64,0 = Garrison Structure
end result would look like this
[01000000]
0=3,10
1=64,0
Name=Whatever
Now remember that FA2 editor does not have this option so if you load the map in the editor after doing this and then save the map again, it will overwrite that 64,0 into 3,0 and you will need to edit it again inside notepad or the text editor you used.
Test and you will see what im talking about or just get FA2sp Here and you can just do its like normal in the editor