the red line goes to manifold vacume. the blue line is left open with a filter on it as a breather. the green line is for 2 wheel and goes on to the "top" of the vacume motor. the yellow line goes to the side and has the funky 2 thing. there is a black line that is paired to the yellow that gets routed to the firewall that does the 4x4 switch that turns the lgiht on the dash on. the connector on the T-case should be a one way thing.