Just a quick note that if your UCP compatible JSGME add-on mod requires removing stock game files, all you need to do is to include an empty version of the file you want to remove and tack on '-remove' to its file extension (thanks to darkcyde for the tip):
If you wanted to remove e.g the file <s2u_install>\some\folder\yourcarname.vhf.bml, you'd include an empty file called named <your mod>\some\folder\yourcarname.vhf.bml-remove in your mod folder structure and JSGME will take care of creating a backup of the file in question and move it out of the appropriate <s2u install> folder.
This makes the install process mostly hands off, which is usally a 'Good Thing(tm)', as you will be testing the same install experience as your users will see.
In fact, the UCP itself includes a couple of such files in <s2u install>\MODS\<UCP folder>\TOCFiles\ if you want to see a working example.
P.S. Thank you for the wing, JDoug!
P.P.S JDoug, if you are poking around in S2U and the UCP, perhaps you could let me know if there are more files that you'd personally recommend unpacking and dummying out in addition to the ones that we already unpack?