HD textures

[Corso]

There is https://p99.yourfirefly.com/ (lowres_s3d.zip, highres_s3d.zip and x4classicUpgrade.zip especially) and then there is https://wiki.project1999.com/EQClassicHD and https://wiki.project1999.com/Highres_4X_HD (among still others).

My goal is to have a classic looking game (no custom/cartoonesque bullshit), but upscaled textures wouldn't hurt, and I'm still confused as to which one(s) I should install and in what order. For instance, should I just install highres_s3d.zip, or should I install lowres_s3d.zip first and then highres_s3d.zip? What about EQClassicHD and Highres_4X_HD?

Sorry if it has been answered already, I've searched the forums for a straight answer but couldn't find it.
Thanks to anyone willing to enlighten me!