So my current setup in the Trans Am...

Head unit: Pioneer DEH-P6000UB
Front speakers: CDT CL-61.2 components
Rear speakers: CDT HD-6MDVC 6.5" subs
Subs: (non-sponsor link removed)
Sub Amp: Viper D1200.1
Speaker Amp: Stock Monsoon amp
Sub Box: SubThump T-top box

Here is a shot of the box and my subs:
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So my amp blew last summer because it sat in inches of water after my hatch was popped up (slightly, it wasn't latched all the way) while it was getting worked on and left outside in the rain. So the amp is gone. The subs still work fine, but I am thinking they are overkill and want to replace them with something different.

Right now I am thinking of replacing the top of the box with a new piece of MDF, and getting a 12" circle sub that sits in the middle. And then mounting two amps, a sub amp and a speaker amp, on either side of the sub. I'll have to do some measuring, but I think some of the smaller amps can fit. I know Massive Audio makes some tiny amps, and they are decent. I was thinking about recessing the amps into the box, and trying to hide all the wiring as best I can.

Another option is to get a Rear Wall Amp Rack and then go with a smaller 10" sub in a Driver Side Stealth Enclosure. This doesn't have much volume though, and I'd rather keep the box I have now as I like the way it looks.

Any recommendations for subs? The L5s were loud, but they weren't very clear. I really just started looking and am not sure what is good anymore. Also looking for amp recommendations. I guess for the sub amp I'll need to pick a sub first, but for the speaker amp I'll need something close to the speaker specs. The front components are rated for 160W @ 2-ohm. The rear "subs" are DVC, so I can wire each 4-ohm speaker in parallel for a final impedance of 2-ohm. So 70-150W @ 2-ohm for those. So I guess a 4-channel amp that can output ~150W @ 2-ohm would be best.

Any other recommendations?