Stock amp with aftermarket speakers?

[PyreX KinG]

So i just ordered myself sum;

Kenwood eXcelon KFC-X693 6x9's

http://www.sonicelectronix.com/item_22938_Kenwood-eXcelon-KFC-X693.html

Kenwood eXcelon KFC-X133 5" 1/4

http://www.sonicelectronix.com/item_22941_Kenwood-eXcelon-KFC-X133.html

I plan on putting them in my 97 Cadillac Eldorado ETC. I decided to take a look at what i'ma be needing to do to remove the stock 6x9's and noticed that they have a factory amp attached to them. I've never seen anything like this with my previous cars or any friends that i've worked on.

So my question is if i can & and ifso, should I use them with the kenwoods?

also, just ordered this headunit:

Kenwood DDX318

http://www.sonicelectronix.com/item_33449_Kenwood-DDX318.html

here's sum pics of the amp.

if ya need any other pics or anything. lemme kno.