On a recent trawl for documentation on the 6100 DOS card, I found this (on the Houdini card FAQ):
The DOS card can share one monitor attached to both cards via
a Y cable or it can independently drive a VGA, Apple 13, 14
and 16" monitor. The connector is a standard Mac 15-pin
connector. If you use one monitor, the image jumps when you
switch but Apple has an option to fade the Mac screen before
this happens. When you use two screens you can see both update
simultaneously, but when you are in a DOS environment the Mac
screen is always slightly dimmed. I tried connecting two Apple
16" displays (one the Mac and one to the card) it worked fine.
In fact, with the correct Windows drivers you can easily get
800x600 on the Apple 16".
The FAQ was written primarily for use of the card in the Quadra series, but it might be worth seeing if a monitor can be made to work without the 4-headed cable once you get the machine.
The DOS card can share one monitor attached to both cards via
a Y cable or it can independently drive a VGA, Apple 13, 14
and 16" monitor. The connector is a standard Mac 15-pin
connector. If you use one monitor, the image jumps when you
switch but Apple has an option to fade the Mac screen before
this happens. When you use two screens you can see both update
simultaneously, but when you are in a DOS environment the Mac
screen is always slightly dimmed. I tried connecting two Apple
16" displays (one the Mac and one to the card) it worked fine.
In fact, with the correct Windows drivers you can easily get
800x600 on the Apple 16".
The FAQ was written primarily for use of the card in the Quadra series, but it might be worth seeing if a monitor can be made to work without the 4-headed cable once you get the machine.