dude, if you are on a budget and want great sound look at JL Evolution speakers. I have them in my whole car. And they sound great. You can do the front and back for $300. I dont have monsoon though either.

And no, you have 5.25 in front and 6x9 in front......
You would need a whole rear set still.

Look at these... great value, product and price.

you need 5 1/4 for front and 6x9 in rear.
Front: http://mobile.jlaudio.com/products_c...php?comp_id=60
Rear: http://mobile.jlaudio.com/products_c...hp?comp_id=128