Audio Systems: 98 eldorado non\bose stereo, electric antenna, cadillac dealer

Question
my 98 eldorado has a non\bose am/fm cassette deck with a remote radio receiver mounted in the trunk behind the rear seat, I purchased a chilton book on my car to help me with finding all the wires for installing aftermarket amps and speakers, well it does'int show my remote receiver, it shows mine mounted next to the electric antenna on the pass side rear quarter with different plugs and the antenna pluged into it, my receiver is behind the seat and the antenna plugs into the head unit. I'm trying to find out if the wires going to the speakers come from the head unit or come from this receiver in the trunk. I tried talking to my cadillac dealer but they are short with me and have no answers I'm 21 and look 17 so I'm guessing thats why they are so rude to me so I'm not getting any help from them. any help is very much appreciated or any ideas on how to figure out where the speakers get there signal from would help me out.   I plan on running the wires that goto the speakers into high to low converters then with rca's to a 4/chan amp and from that amp with rca's to another 1/chan amp for my sub. Thankyou in advance

Answer
Well, your age should not be a factor (especially as kind as you are)! But the type of advice you about to incur is not likely to be heard at a dealer, either  ;)

*Since you have told me some of your plans, I should just say this now...  get RID of that entire system and start over. Though it takes some time, by doing moderate upgrades in logical progressive stages, you will have astonishingly better overall sound in little time [and without that bad boy price tag].
This kind of thing is one of my fortés.
You have the right idea up front, you already have a different deck, keep pulling the Bose stuff as fast as possible!
Stop trying to polish that terd and flush it!


OK..ok!   before you hang up on me...
Here is what I suggest in the short term:

Run ALL new speaker wires where you need them (from you new amp to each speaker), then you can use the decks RCA's [if yours does not have RCA's get one that does] right into the new amp, way better .. I cannot stress this enough. You sound quality, overall accuracy and dynamics will be totally and noticably better than if you use line convertors.

If that is not possible  :Now, as to 'what wire is what' in that mess (by now, you know it is a mess  lol), try looking at the back of the speakers then write down the color codes for each. You should be able to match these colors up with one of those two devices you have there.
If memory serves me, the wires come from that remote one and are line level (The speakers used to have the amps on them glued into the back). Not sure on the 98.
I do know that you should just run new stuff instead of trying to interface. Maby  for now, but run new wires when you get the new amp.

Hope this helps.
Best of luck,
Jm