[mikegett]

wrightie, a LOC (Line Out Converter) is what changes a speaker wire (high level) to rca (low level). That is why they have been discussing LOC's for the past four threads. And the stock HU does not have a line out converter built into it. They run high level straight back to the speakers or monsoon amp. I will agree that most aftermarket HU's will sound better, but a decent LOC will make your factory sound pretty good as well. The key to amping off a factory HU is to use as little gain from the HU as possible. Keep it at half volume to eliminate all of the internal noise. Then raise the LOC's gain to compensate for the reduced HU volume. Since you are using the LOC's gain to aquire a higher voltage the amp should be kept below half on its gain. Preferably one quarter. Otherwise you are just amping a signal that is already amped and hissing will result. ***please make a note that many LOC's can produce up to 16 volts. Most amps will only accept up to 5 volts before the inputs fry.******
You have two options with hooking up the amp. If you do not use the rear speakers then do as mike suggested and go directly into the high level inputs of the amp. If you are going to use the rear speakers then place a LOC in line. You will need one that allows the original speaker wattage to pass through unharmed or loss in power to the 6x9's will result. Sosche makes a very nice one for about 35 that will do this. Keeping the 6x9's will be your call. I would personaly keep them unless you have a nice set of componants in the front. Otherwise your sound stage will be very week.
Here is option for eliminating the turn on wire. This will wire right to your speaker wire and send a 12 volt signal to your amp for turning on. They come in handy in situations where you don't want to remove a HU.
http://www.cardomain.com/item/PERLVT2
This is a option for eliminating the poping of a amp that does not have soft turn on capability. I suggest always trying the amp prior to buying such a expensive part. You may get lucky and have it built in.
http://www.cardomain.com/item/PERVT3
Here is a decent LOC you should be able to find at best buy. At the least buy one that has a full DC isolation. Stinger makes some decent ones as well. Just be carefull to avoid setting the gain too high as I stated before. If you have a meter then you can set the voltage to match your amps max input value.
http://www.scosche.com/scosche.aspx?Catego...=36&ItemID=SLC4