1998 Ford F-150 Wiring Problems

I have the converter hooked up, and I tapped into the speaker wires after the amp, I THINK.  The amp is behind a panel, and I could barely remove the clip.  I cut into all the speaker wires, and it didn't work.  There was no sound at all.  I'm not sure, but I just thought of this... If I cut into the wires AFTER the amp, but BEFORE the deck, that still wouldn't work, because there can't be the factory amp and the aftermarket one, right? 

I think my main thing right now is to either find a different spot I can get to the speaker wires, or try and get all the panels off and get behind the factory amp.

No if you use the factory HEAD unit (radio) you will need to use the factory amp as well. So you will have your radio then the wires go to the factory amp. You need to tap into the wires to get a signal for your aftermarket amp after the factory amp. So in order for it to work you need both the factory amp and you’re after market amp. Also where are you getting power for your remote wire for your aftermarket amp? Also might want to remove the panels around the factory amp so you can see what you are doing. Let me know what happens.

Sounds good. Try and hook up the high to low converters after your factory amp and  let me know the results.

Just checking to make sure, but a friend told me that I can't hook up the factory amp and the Kenwood amp.  I don't know how much he knows, but he is a certified installer at a local shop.  You still say splice the wires in with the factory ones? 

The converter isn't the problem, the only problem is where to hook up my wires from the Kenwood amp to the factory radio.

Ok you need to splice into the wires coming out of your factory amp that would normally go to your speakers. Now cut all 8 wires (4 channels) that come out of the factory amp. Now tie in your high to low converters to the wires you just cut coming out of your factory amp. You should then run your RCA cables from your high to low converters to the  aftermarket amp. That will supply the amp with an incoming signal. Now to hook up your amp (aftermarket) to the speakers you can either run new speaker wires from the amp (aftermarket) to each speaker (recommended) or you can tie them back into the wires that you cut that go to your speakers. Also remember to run your power wires on the opposite side of the car as your signal (rca, speaker wires) cables to avoid any interference( engine noise) hope this clears things up if you need any further assistance don’t hesitate to ask.

Well the problem has been fixed.  Although I didn't take the advice posted here, I still appreciate the help.

Allow me to specify what happened in case anyone else comes across this problem.

You have to splice into the wires BEFORE the factory amp.  So for the front left speaker, I went into the driver-side kick panel and spliced from there.  For all the other three speakers, they are all in a harness in the passenger-side kick panel.  The back speakers both run along the passenger door sill and into the kick panel.  I just spliced into the remaining ones here, and used a hi-low converter and put it in the passenger kickpanel. 

It all worked out, and the help from the forum helped me understand what I should and should not do.  Thanks all, I'll be back. =)