To retain the stock radio in my Thunderbird and improve sound quality, tone and loudness I am thinking of getting a stand alone 5 to 12 band equalizer to run the speaker wires to then from there either to the speakers (which are new) or to a small amp (<200W) then to the speakers.  Looking at e-bay I could get an equalizer for around $25 and each amp (need two, front and back) for about $25 each as well.  I was just wondering if anyone had ever set up a modern aftermarket equalizer and amp with a stock radio from the 60's?  It's a stock AM/8-Track radio with front to back and left and right fader controls to which I run either an MP3 player or CD player through the 8-track.  

Uh...no.  Shouldn't be a problem...I hope.  It should be pretty straight forward.  I know that my amp needed a source wire...but I think thats just a splice from the power to the head unit...so when the head unit is on, the amp is on.  But I can't remember for sure...

I know that at least Rockford Fosgate offers a unit that converts the signal from the factory stereo to a setup that is more component friendly.

Its out of your price range, but you might go ahead and check it out.

Rockfordfosgate.com  The unit is under the products, then processors (I believe) and is called 3Sixty.  I'm a big fan of Rockford Fosgate stuff.  I've got a pair of Punch Zs (absolute bottom of the line subs) from 5 years ago...still sound great (sound great...not POUNDING...but great quality of sound).

I didn't know you could adapt into an 8-track...good to know!  

I've installed sound systems before. I got an 800W amp and two 12"'s in my Centurion and a 450W" and two 10"'s in my Skylark.  I know a couple people also that swear by Rockford Fosgate too.  Back on track here, the sound systems I've installed always had a dedicated Amp out plug, and I know at least some amps are input voltage sensitive, to which I have no idea what the output voltage is on the radio, but I think the low wattage amps (like 250w) are designed to go straight from the radio feed to the speakers.  My main question mark is in reference to the equalizer really, will they work with an amp or is it better to go straight to the speakers?

Found on E-bay an 8-Track to Cassette adapter, to which I applied a Cassette to Headphone jack adapter to which I plug into the MP3 Player, FM Tuner, Discman, it sounds pretty good, but certain ranges just aren't there.  

It will work with an amp...I'm 90% sure of that.  I have a little 200W Pioneer (uhhhhggggggg) that I use to power my 6X9's...and that just takes the speaker wire from the head unit.  Going to the equalizer first, at least to me, seems like you're using two components to do the job that one does with an aftermarket CD player (output signal + conditioning).  So I don't see why there would be a problem.

I'd try it if it were mine.

Good luck  

Sounds reasonable enough, hooking the head unit wires to the amp sounds like what I wanted to know.