Base stereo upgrade

C Haller

Hello everyone! I just bought a 2013 Nismo 370z (my third 370, one was totaled in a wreck and the other I traded in for the Nismo) and of course I want to upgrade the stereo system. I’m not looking for a world class sound system, just something that will sound as good (and maybe a little better) than the Bose I had in my last Touring 370. Also, I am not trying to be cheap but would like to keep the costs down. I don't plan on adding a sub or amp to keep the install cost/time down. I plan to do the install myself with the help of a friend and I just needed some help picking out all the hardware I need. Here is what I have so far:

Pioneer AVH-X5500BHS
Axxess Metra ASWC-1 Universal Steering Wheel Control Interface with New Micro B Connector
Parking Brake Override Bypass
Polk Audio DB6501 6.5-Inch 2-Way Component System (Pair, Silver)
iSimple IS335 Dash Mountable Auxiliary Input Adapter
PAC 6' USB Cable with Mounting Bracket USBCBL

I got the AUX and USB jacks to mount in the center console or where the heated seat controls would be. The few questions I have are:

1. Should I upgrade the dash speakers too? If so, what would people recommend?
2. Am I missing anything to complete the install?
3. Do I need a special tool to remove the stock head unit?
4. Will I be alright without an amplifier? (Again, I'm not looking for a world class system here)

Thanks in advance.