Welded Diff
 

Does anyone have a diagram of what needs to be welded in welding the diff on an fc

To turn the open diff into a solid diff, weld the gears that are on the shaft that spans the the middle of the diff perpendicular to the halfsharts to the gears that the halfshafts connect to. Be very sure that this is what you want to do before you do it as it's irreversible.

if you have to ask
dont do it

Are you taling about welding it to the subframe so that its solid?

I wouldn't recommend doing it on a street driven vehicle.

It's cool as hell if the welds break and get caught in the ring/pinion. :) I love watching when that happens!