NOTE: I do not know for sure if this requires a mod to work, these files were available to edit from the GoG package.

1.) Open the file cam_ext.cfg found in your System Shock 2 folder with any text editor of your choice.
2.) Change the following;
mipmap_mode to 0
tex_filter_mode to 0
multisampletype to 0
3.) Place ; before;
tex_filter_trilinear
square_parts_as_disks
pixel_parts_as_disks
4.) Remove ; then change;
movie_sw_scale_quality to 0

Other useful options are, in the same configuration file;
Field of view - ctrl + f fov and change 90 to whatever you like.
High resolution timer - I will be honest, I don't know what the fuck this is but it didn't break the game so uncomment use_hi_res_timer and check it out.
HUD scaling with resolution - Enable by removing ; in front of d3d_disp_scaled_2d_overlay 64
Remove mouse acceleration - Paste use_raw_mouse_input at the end of the config file.