8 Speaker Stereo Issues...., NEED SOME HELP!! Options

[Silver94CelicaOw...]

I have a 94 GT with the double-din, 8-speaker premium audio setup that has an amp built in to it all. My stock CD-player doesnt work anymore....it doesnt read the CD correctly, so i decided to replace it.
Noww....I spent almost the entire day at Circuit City trying to get a 50w x 4 Panasonic head unit installed into it, only they said that they cant install it because of the 8 speakers and how it wires up.....the wiring harness doesnt work because of the amp. The guy i dealt with was an honest guy, but he said that for it to work, he would have to install two more amps to power the in-door subs up front and the two tweeters. Apparently the head unit could only power the front two mid speakers and the rear two without running into any problems with the ammount of OHM's each speaker was recieving.....thus, no splitting wires to power the subs and tweeters unless i wanted to blow the head unit. i was quoted almost $950 total for the head unit, installation, and amps alone.....just to get the stock speakers to work correctly!!!

So here are my questions-

1.) Does anybody else have the 8-speaker system and gotten a new head unit?? If so, how did you fix it???
2.) Is this guy right??
3.) Should i just get a new double-din unit from Toyota that i can just swap to avoid all this, or is there some way i can fix my existing head unit??

Any help will be greatly appreciated......ive had a long day, and i need some knowledgable people to set everything straight for me. Thanks.

-Corey