The manual is identical to the PC-9801 3.5 inch version except for the front cover and page 27. There are two versions of the manual: one where page 27 references the X68000 directly, and one where page 27 is the same as in the PC-9801 manual but with a sticker hiding the reference to PC-9801 and replacing it by X68000. Both pages are shown here.
See also:
How to play X68000 games under Windows? (Dungeon Master and Chaos Strikes Back)
What is an X68000?