To install the patch, backup the files: BERET.EXE and LEVELS.MRF in the directory that you installed Spec Ops II.
Unzip the patch, copy either D3D.EXE (Direct3D) or VOODOO.EXE (3dfx Voodoo) into your Spec Ops II directory. Rename D3D.EXE or VOODOO.EXE to BERET.EXE. Copy the updated LEVELS.MRF into your Spec Ops II directory.