@LRNSR
I'm glad to hear that. Essentially you unzip (7z) the OIV because it's an archive just like any zip or rar or 7z file. Once extracted, inside will be a folder containing all the contents - all the files that will be installed. You can actually peek inside without full extraction.
Files you definitely don't want to install are dlclist.xml and gameconfig.xml from the OIV - assuming they are in the package, which I don't think is the case.
Where the files will be installed is spelled out in the file called assembly.xml. This is a text file with the instructions for the OIV, as to what to install and where. You use this file for the manual install. Ofc you could modify this file, remove crap, repackage it, and install with the OIV but that's not necessary.
This article will hopefully help: Installing with OIV - The Safe Way
If you have difficulties, post the assembly.xml here and regardless, backup key files like update.rpf.
Edit: In the video, which coincidentally is one version of LC, the package contains files like SHDVD which obviously you don't want - because they are old, outdated versions. Same logic goes for similar files. The heap hasn't changed in years but the packfile was updated a few years ago.