That black line goes from the vacuum control valve on the side of the IP ( different from the vacuum control unit stop on top of the IP) to the interior of the car under the dash. It is a vent line open to air inside the car. Maybe you can push it back through the firewall.

Performanceproducts dot com catalog lists the 201 FSM CD for $60, and the Haynes 190E manual for $18.

An ebay seller is selling the paper 201 chassis and body FSM and the 102 engine FSM as a set for $130 shipped.

Also on ebay is a dash overlay plastic piece, and also a carpet cover for the dash (I use one myself to hide the cracks).

I have a very lightly used 201 chassis and body FSM, and an extra coil bound photocopy of the 601 engine FSM. Yours for $50 shipped. PM me if interested.

Are you related to ps2cho?