Stock Stereo Setups, Trying to figure things out Options

[Fastbird]

Ok, after searching and not coming up with anything clear cut:

What are the factory soundsystem setups, I.E. head unit combinations, speaker setups, amps??, speaker sizes, ect.

I'm mainly trying to figure out what exactly I have in my 99 GT so I can rip them out and throw in better things. I plan to stick with the stock size and throw a sub in the back (probably a single 12, not sure yet).

I have what looks to be component speakers in the front doors, but I haven't taken a close look at the rear side speakers yet.

Can I get some guidance please?? Usually crutchfield is pretty good about showing what's in there, but it blew chunks this time.

[Fastbird]

My setup is as follows:

Double din factory head unit: Top half is tape player, bottom half is CD player. Component speakers in the front doors with the tweeters located on the back panel to the mirror mounts, and I haven't a clue what the back side panels house.