Download the Streamdeck app installer (https://www.elgato.com/us/en/s/downloads)
Download UniExtract2 (https://github.com/Bioruebe/UniExtract2/releases/tag/v2.0.0-rc.3)
Extract the UniExtractRC3.zip and you should be greeted with a UniExtract folder containing the following files/folders.
Open UniExtract.exe and drag the Stream_Deck_X.X.X.XXXXX.msi (Stream_Deck_7.0.2.22062.msi at the time of writing this) into the UniExtract window which should autofill the 2 boxes with the path of the installer and the extracted path you want to use (You can change this to your liking).
Hit Okay and it will begin the extraction process before opening up the folder that you specified for the output.
In here you will find the Elgato and obs-studio folders. Elgato is simply for the Streamdeck app and of no importance.
Navigate to obs-studio\plugins\StreamDeckPlugin.
The files from StreamDeckPlugin\bin\64bit go in
...\obs-plugins\64bit\StreamDeckPlugin.dll
...\obs-plugins\64bit\StreamDeckPlugin.pdb
The entire contents of the data folder go in
...\data\obs-plugins\StreamDeckPlugin\StreamDeckPluginOBS32.dll
...\data\obs-plugins\StreamDeckPlugin\StreamDeckPluginOBS32.pdb
...\data\obs-plugins\StreamDeckPlugin\StreamDeckPluginQt6.dll
...\data\obs-plugins\StreamDeckPlugin\StreamDeckPluginQt6.pdb
...\data\obs-plugins\StreamDeckPlugin\locale\
The following files are designed for previous versions of OBS and not needed for these instructions or any of the last couple major versions of OBS.
StreamDeckPluginQt5.pdb
StreamDeckPluginQt5.dll