Simpson from Hong Kong has just successfully modified a Pioneer DV-S838A with the PMS SDI mod. kit. Congratulations!

This is the VQE board.

Closeup for pin assignment:

Opposite side pin assignment:

The DJK board (get 5V power here):

Wires connected:

Opposite side: (please note that the clock wire is twisted with the clock ground)

Then mount the SDI kit:

Rear view:

Well done!