The computer has a removable SCSI HDD case to change it easily. I replaced the old SCSI HDD with Henkan Bancho.
I have installed the following graphics board, Canopus Power Window 928II, and LAN board, BUFFALO LGY-98, to run Microsoft Windows 3.1 and LAN Manager.
I used the graphics board with IO-DATA LCD-AD191SEB, and so I could display the screen normally without the special settings because the LCD display supports a legacy screen mode, 640×400, for PC-9801 series.
I have installed Microsoft Windows 3.1 on NEC MS-DOS 6.2 with some development software such as MS-C 6.0 and MASM 6.0 into to the new SD card.