The line you have labeled "dead end" should be connected up to the line that goes to the vacuum pump, which you have labeled "to booster". The to booster line looks like you have an connection without a plastic vac line hooked to it. I would plug the check valve (the blue and black plastic thing) to the unused connection. It also looks like you will need to replace the 4-way connector on the dead end line, it is split so it may be leaking.
Try looking at the vac diagrams on Skinnerbox shop manual webpage. They may be helpfull as well.

Looks as if there may be leaks in your doorlock system, and that why someone unplugged those yellow lines, and sealed the system with golf tees. I believe the brown/blue line is the engine shutoff, so you may have a leak there too, and that why that one is unplugged.
Hope you get it worked out.

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