90 dakota 4WD motor vacuum lines -HELP
 

I have a 1990 Dakota 3.9 v6 and 4wd. After not being able to get the 4wd transfer case locked in, I looked in the factory service manual and I see where there is a motor that is vacuum operated that I guess engages the 4wd. Well, my vacuum switch has 2 short hoses that are plugged with bolts.

I need to know where exactly these vacuum lines connect on the top side of the engine. To my surprise the factory service manual does NOT show where they connect.

Can somebody help me out?