If you wnt three way components in the front be prepared to get the fibreglass out!
Best course of action is to fit 2 way components. If you use a 6.5 inch speaker you can mount it to the door card itself and put some mdf behind the card for good bass
Are you looking to amp the speakers or just run them off the HU? If you are looking to amp yu should really replace the speaker cable for some OFC if running off of a hu just use the existing wires, simple job then!
Plus while you have the door card off spend £40 on two sheets of sound deadening and do your doors, you will be amazed at the difference in sound of your speakers and the reduction of road noise as well!