There are approx 1404 p3d models in the game.
553 of these have classnames because they are configured in one or more config files.
The rest, 851, have no config entry anywhere and so have no classnames.
You need a classname to use a model in the mission editor, which is what the various editor upgrades do, they configure most models that have no classnames, thereby giving them a classname and making them available for use in the editor.
There is a resource available that lists p3d files and their associated classnames from the game config.bin.
It also lists the models with no classname.
Get it
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