mk3/mk4 tranny swap

I was doing some searching and I found out that the W-58 tranny was used for both mk3 and mk4 N.A. motors. That would lead me to believe that, with a custom driveshaft, you could put the 6-speed (forgot actual name) tranny in a turbo mk3. If this is true, would I have to worry about the gearing ratios between the tranny and LSD?

no one knows?