Lordy, that looks like the remains of a bad LPG install, chuck it away, the car might go faster without it :dance:
As for the cable, you might need a manual for it some time ;) but it should loop around the air flow meter and connect to the brakcet behind the plenum inlet, it pulls to the top of the throttle spindle IIRC but it's slightly different to the 3.9 so I'll have to check.