planned pioneer set up in a '98 mustang

Hey folks I'm new here and new to the Car Audio World. I'm hoping I can get some insight from all of you on a few things and perhaps any questions I run across during my installation. Last summer my stock CD Player stopped working on me in my '98 Mustang. I decided to save up and buy a semi-nice system and perhaps upgrade my car as well. Nothing to fancy just try and restore most of it but my hour long drives to and from school can get a little lonely even with the radio. I'm sorry, I'm babbling. To my point; Going through these forums I have come across much. I understand there are many other better HU than Pioneer but I have been pretty set on what I am going to get. I want to ask you guys to see if my planned setup will work well. I plan on getting a Pioneer DEH-P9800BT HU amplified by Pioneer's GM-6300F into 4 Pioneer TS-A6881R Speakers. And eventually down the lines go with a TS-SW2541D Sub powered by the GM-7300M Amp because I would like to keep some trunk space. I know that an entire Pioneer setup might be cheesy, but I'm looking for a replacement for the stock system ant the equipment I'm getting at dealer price so everything is half off which is why I chose the setup. In the end I do want to make sure the four channel amp and 4 speakers will work fine together. If it's easier for me to post their specs I will. Another question I have is the head unit install. Since I have a CD Player as well I have a lot of extra wires connecting from the HU to the CD Player. My question is when I do the install all those extra wires won't be needed sine I'm taking out the CD Player. Currently when I disconnect it I get a drop in power and volume. I'm assuming the stock setup will be useless since the new setup has what is needed. Thank you guys so much, even if you read that entire thing. If any part needs some clearing up and if you need wiring scematics I do have a few. I appreciate any advice."God invented man, and man invented the metric system."

- Salvador Dali

Anybody? Anything? Advice? Critics? Flame?"God invented man, and man invented the metric system."

- Salvador Dali

Everything that you have picked should work fine together. You are correct that you wont use all of the factory connections from the factory hu and cd player. Basically the only connections that you need to make from the new cd player to the factory harness is 12v constant, 12volt accessory, and ground. From the new head to the amp you will run remote turn on and 2 sets of rca's, then just run your new speaker wire to your new speakers.   One recommendation I would make is to go with a set of components in the front doors. It will be a little bit more work but it will give you a much improved sound over the two ways and you are definitely going to want to add a sub to that setup as it will not have alot of base response.