Welcome to the forums
Have you pressure tested the system? I would want to know for sure where the leak is coming from first, the cross over gasket is a bit of work!
There does not seem to be any YouTube videos on this procedure that I could find.
A factory service manual would be handy to access in this situation.
I managed to find this link, possibly other members may chime in on this one as well.
Here is the link to FSM procedure outlined:
Hope this helps.