Need help with front speaker wiring in 1991 Dodge Ram Van B150. Bought new 6X9 speakers to install in the front doors of my van. When I pulled the old ones I found the wires are coated green and black and they are connected to a snap together (in line fuse?? piece with purple and blue wires. What is the snap together piece and should I leave it there and just connect to the black and green wires? Which wire is positive? The green one ?

 

Green is positive and black is negative (ground.)
The "fuse" is just a 2-wire waterproof connector, no fuse.