I am 95% sure that the pin-out for the Mobo is correct as I tested each one with my multi-meter since I couldn't just follow the traces. The one on the GD-Rom connector should all be correct although I didn't use my multi-meter on every connection, just every 5 or so to make sure that I was still on track. But before you use any of this I would suggest that you test the trace and the point to make sure that you are doing the right one.
I want to add in though that I have done the 50 pin relocation using this information because I had 4 traces that were torn up and my dreamcast IS working.

GD-Rom Controller board side

Mobo Side
So now onto the pin-outs. I would highly suggest that if you use these MAKE SURE TO TEST YOUR CONNECTION FIRST! Make sure that it is correct before you connect anything! I also would suggest to not try and do the relocation of the GD-Rom controller board using only these points! It would be very easy to mix up a point or accidentally solder your wire to the wrong point in which case you finish, plug it in and it doesn't work or you could possibly fry your Dreamcast. Anyways here are the pin-outs.
