2000 Dodge Durango Infinity conversion

I have a 2000 Dodge Durango with the stock CD/AM/FM radio. I want to upgrade to the Infinity sound system that was an option for this car.  I can get the AMP, six speakers, etc but the junk yard will not rip out the wiring harness and connectors from the dashboard, said he wants to keep the dash intact for another buyer. Is there a replacement harness with connectors available for this setup?  If not can I just buy the connectors for the amp and rewire it myself? I'm very handy with a soldering iron and can follow complex wiring diagrams no problem. HELP!!

the amp that you buy in the store and the premium setup infinity puts in dodges and gms are not the same. youd have to bypass the stock amp and rewire the speakers. they all have a common ground and the amp only puts out about as much power as the aftermarket head unit.always looking for new info and willing to give it