Hello thank you for using JA let me see if I can help.
On the amplifier they sell an amplifier kit that will give you the big ground and power wires that I recommend for a good power supply. On the radio the sell and install kit for the dash that will make it a custom fit look and will be very clean set up. They sell it at most stores that install radios. Try Best Buy and is vehicle specific. That plus the other kits you mentioned should be all you need.
ASE Certified Technician
Ase certified Electronics, Brakes, Steering and Suspension