My friend has a 1987 Mercedes 300E, and he's lookin' for an aftermarket HU. He's picked out and bought a Pioneer DEH-P3700M. The only problem is that the install guy at Best Buy said that he'll need two crossover cables. What in the world are they, and why would he need them? Those cables are $18 each, and my friend's really looking for a cost-effective upgrade from the factory HU.
Any advice or opinions would be appreciated; and they'd be greatly appreciated if they were prompt :D as he's going to get it installed or returned tomorrow.