Help hooking up speakers

[amashal]

Every radio I've hooked up before has 2 wires per speaker. A color for each then same color and a stripe. I bought a blazer and it has 4 6x9's and 2 speakers in the door that all cut in and out at will. I looked at the wiring today and off the radio is this

1 red
1 red/white stripe
1 yellow
1 black
Those I know.

The speaker outputs however are only 4 solid colored wires. Green,purple, grey, white. How do I hook up the speakers to that? Do they share a common ground? I will eventually replace it all but I need to do a lot of other stuff to the blazer first.

Thanks in advance for any info.