Install Software 3.1. If you have a version of XFree86 installed already, you may want to move it or delete it. With it unset, the build uses the proper defaults. The index.html file in the docs points to manindex5x.html, but the filename may actually be manindex5.html. If you have KDE2, khelpcenter allows manpage browsing.
Procedures vary for other distributions.
Installing over an old version is probably harmless. At this point, Mesa installed its own version of the glx.h include files over the ones that XFree86 installed. These files explain how to tweak the kernel driver. They were written to fix problems with TNT and TNT2 M64 cards but these tweaks are reported to help the GeForce2 MX also. Copy ttf fonts from Windows into a font directory and add a font path.