There are different ways to replace Isabela's armour but the easiest is, in my opinion, to edit the apr_base.
First of all, you have to unpack the files from vaelsmod's mod. Open pyGFF editor and in the "File" menu, click on "Export all". Select "The Rebel Vagrant's Threads.erf" and click on "OK". In the new window that pops up, click on the "Create a new folder" button. Choose a meaningful file name and click on the "OK" button. Accept to overwrite existing files when you're prompted.

Go to the folder you just exported and open the file "item_variations_reb.gda" with PyGFF. Expand line "0" by clicking on it, then expand line 10003 (G2DA_ROW_LIST). Note down the data found in line "10011" (G2DA_COLUMN_7) and repeat with line 1 (rows 298646...). "arm_rbla" is for the grey outfit while "arm_rblb" is for the tube top version.
Now use pyGFF editor to open the file "2da.rim" that is located in "your_game_directory\packages\core\data". Scroll down until you find the file "apr_base.gda" then select it and click on "OK".
In the new window, expand line "0" by clicking on it, then expand line 10003 (G2DA_ROW_LIST) and click on it to highlight it. In the "Edit" area at the bottom left of the window, delete all lines except "1050, 'Follower - Isabella'" and "1051 'Follower - Isabella'".

Go to the first remaining line ("1050, 'Follower - Isabella'") and expand it. Click on "10008" (G2DA_COLUMN_4) and go down to the "Edit" area.
Replace the last part of "art\characters\playercharacter\humanfemale\bdy_isa" with the data you found in the item_variations file. You should end up with "art\characters\playercharacter\humanfemale\arm_rblb".

If you want to replace Isabela's romance armour as well, you'll have to edit the line second line too. Click on line 1 to expand it, then select "10008" (G2DA_COLUMN_4) and go to the "Edit" area.
Replace "art\characters\playercharacter\humanfemale\bdy_isab" by "art\characters\playercharacter\humanfemale\arm_rblb" and click on the "Save" button.
We are done, so go to the menu bar and click on "File". Select "Save As" and change the file name to "apr_base_anythingyouwant.gda" then save. Just be carefull not to overwrite the original file.
Put your modded file in the folder where you extracted the file "The Rebel Vagrant's Threads.erf". The files "arm_rbla.uti", "arm_rblb.uti and "arm_rebel.ncs" aren't required so you can delete them.
Then copy the whole directory where you installed "Erfpack-rev21" then drag and drop it onto the executable (Gibbed.Bioware.ErfPack.exe).

Put the the generated .erf file into your "\BioWare\Dragon Age 2\packages\core\override" directory and launch the game. Isabela should now look like this:
NB: bear in mind that there will be a conflict with any another mod changing Isabela's outfit.
In case you need it, you can also make Isabela wear an armour with multiple pieces by editing the apr_base in the following way:
Expand line "0", then line 10003 (G2DA_ROW_LIST) and then expand line "0" ("1050, 'Follower - Isabella'"). Go to line "10008" (G2DA_COLUMN_4) and delete its content. While this is not mandatory, I think it tends to avoid confusion with edits of one-piece armours.
Now go to line "10009" (G2DA_COLUMN_5). In the "Edit" area, replace H with P then click on the "Save" button.
With PyGFF, open the file "item_variations_
something.gda" that is located in the mod you want to use. Expand line "0", then line 10003 (G2DA_ROW_LIST) and note down each number found in line "10005" (G2DA_COLUMN_1).
Go back to your apr_base file and scroll down to line "10096" (G2DA_COLUMN_92) and click on it. In the "Edit" area, type the first number you found in the item_variations file and click on the "Save" button.
Go to line "10098" (G2DA_COLUMN_94) and click on it. In the "Edit" area, type the second number you found in the item_variations file and click on the "Save" button.
Then go to line "10100" (G2DA_COLUMN_96) and click on it. In the "Edit" area, type the third number you found in the item_variations file and click on the "Save" button.
And finally, if you want to wear a helmet or a hood, go to line "10102" (G2DA_COLUMN_98) and click on it. In the "Edit" area, type the fourth number you found in the item_variations file and click on the "Save" button.

When you're done, go to the menu bar and click on "File". Select "Save As" and change the file name to "apr_base_anythingyouwant.gda" then save.
Put this file in the folder where you extracted the mod files and repack it with Erfpack-rev21.
Happy modding!
Edited by Makacha, 21 October 2020 - 06:24 AM.