You need to find an external Scan Doubler/Flicker Fixer, or
a Zorro Graphics card that has the SD/FF built-in. The best
is the Picasso IV, but make sure it has the SD/FF, as some
of them do not (apparently). Other options do not allow the
Native screen to be displayed on your modern LCD screen.
Hope that helps, and congratulations on your A4000.
(make that congrats to both of you new A4000 owners)