Okay, as suggested, I deleted the ALP-46 directory and all files and subdirectories in it.
I have the following installation files:
Amtrak ALP-46 Expansion Pack V1.0.rar
ALP-46 Train Pack V1.0.7z
NJT ALP-46 Train Pack (Complete Exteriors) V1.0.rar
NJT ALP-46A Pack V1.0.rar
In what order should I install them?
Mike
It doesn't matter. All of the .rar files are made to be independent of each other. Keep in mind the file hosted on the BVE station site is only the ALP-46 (just the NJT version). On my mediafire site are the other three versions (the alp-46 for amtrak, the alp-46a for amtrak, and the alp-46a for njt).
ie, the two files you stated above ("ALP-46 Train Pack V1.0.7z" and "NJT ALP-46 Train Pack (Complete Exteriors) V1.0.rar")
are the same thing.
Once again, to install, simply open up the .rar file, and drag the file folder into your trains directory.
(openBVE/trains/)
And as stated before, no overwriting should be necessary if you've already deleted the previous files from your directory.