Quote:
where is best to tee back in from turbo coolant out back into 1200 cooling system
Where Nissan teed back any coolant lines was the suction pipe. Heater hose goes back to there, water-heated manifold goes back to there.
If you currently have one- or none- inlet suction pipe, replace with a two-inlet suction pipe
one-inlet suction pipe

two-inlet suction pipe

You can also add a B110-style suction tee into the lower radiator hose
