Apple Video System - Manual (Page 9)

Your compact computer may look like either of the
computers pictured below; the steps for installing the
card vary slightly depending on which model you have. If
your computer looks like Style A, follow the first set of steps
to install the video input card. If your system looks like
Style B, skip to the second set of steps, “Installing the Card
in Style B.”
Style B
Style A
3 Installing the Card and Software and Connecting Video Equipment