reccomendation on wiring/new subs

Hello,

I have purchased a Audiobahn A18000X and (2) Audiobahn AUDIOBAHN AW1251M 12" subs.

Amp Specs:
A18000X

Power Handling:
1 x 1000 Watts @ 2 Ohms
1 x 500 Watts @ 4 Ohms
Peak: 2200 Watts
2 Channel Amplifier
PWM MOSFET Power Supply
Variable Hi/Low Pass Crossover
Bass Boost
Subsonic Filter
3-Way Protection
Cobalt Blue Illumination
Nickel Plated Connections
RCA Throughput Connections
11 1/8î W x 2 1/8î H x 11 7/8î D
1 Year Manufacturer Warranty

Sub Specs:
Peak Power Handling: 880 Watts
RMS Power Range : 400 Watts
Multi-Connect Lug Lock Terminals
Non-Pressed, Non-transfer paper cone
KM3 Coated for virtually no cone distortion
Flame Stamped Strontium Magnet w/ Faraday Cage
Dual 4 Ohm Voice Coil
Frequency response: 24-1000 Hz
Sensitivity: 92.1 dB
Magnet Weight: 45 oz.
Mounting Depth: 5-1/4"

I have them wired in:
Option 2 (series/parallel) = 4 ohm load
Voice coils wired in series, speakers wired in parallel
Recommended Amplifier: Stable at 4, 2, or 1 ohm mono

Im wondering what would be the best wiring method to amp for most power and deeper bass. Right now it sounds like its bottoming out when i turn it up. And lower volumes, the bass sounds nice but the deeper stuff I cant hear to well. Also, if this helps they are in a large slotted box together. Any help would be greatly appreciated. Thanks.

If I was to run it this way, would I get the most power?

Found this image on the net