Since I've been receiving many emails on this subject, here is the key information everyone needs for the modification. If this does not make sense to you, most likely you should not be doing the mod! ;-)

Attach the serializer to points corresponding to the Analog Devices ADV717x Video Encoder located on the output board. For 596, 598, and 800 interlaced models, the encoder is the same. On the 598 and 800(v2) Progressive models, attach at the interlaced video encoder.

Pin 38 = P0
Pin 39 = P1
Pin 40 = P2
Pin 41 = P3
Pin 42 = P4
Pin 2 = P5
Pin 3 = P6
Pin 4 = P7

Pin 44 = Clock

Regards, Peter