1 You start with the radio:
Looks like the plug is a din-plug? goto the auto dealer and ask for a cable that fits on bouth(car&radio) they must have it.
2 Run some cable's(rca / the red&white) from your radio to amp 1 and from the amp1 to amp2
3 run the cable's from your amp to the speakers.
The GM-X402 is 2x35Watt @ 4 ohms and 2x70 max
The GM-X502 is 2x50Watt @ 4 ohms and2x100 max
So as i remember corectly the GM-X402 is bridgable and i whout use it to drive the kicker box
The four speakers you can place them in line and conect the right and the left to the amp
so bouth the right (front+rear) to one channel and the left (front+rear) to the other one
, driving them @2 ohms (think that the amps are stabile at 2 ohms)
Let me know how thinks are going.