dont use the stock perdana location, its only 4inch and it aims at your feet, bad location
go to a shop that has done many perdanas, so they know where to get the door panel with speaker mount.
get a 6.5 inch component set (comes with mid & tweeter). just concentrate your money on this first, rear speakers use back ori one.
then save money to buy a 4ch amp, and then a sub.... thats all u need for a simple system. its about quality, not quantity..