Well most of it anyways….
I mashed in all you need to build it for MS-DOS under MS-DOS here.
It should be really simple, just run the Watcom C’s setvars, then go into the duke3d\source directory and run ‘wmake’ … All being well it’ll output some exe’s. I’ve also included the shareware data files so you can test your executables.
Not bad for being under 10Mb, compressed.