mono block amps , 4ohm dvc subs

My Truck is a 1999 Ford Ranger Extra Cab

A DVC 4 ohm sub can be 8 ohms or 2 ohms, using both coils.  If you have two of these subs, the impedance will come out to be 4 ohms when you combine them.  Put this 4 ohm combined load onto the mono amp and don't worry about getting that li'l bit of extra that you might get with the 2 ohm impedance.

Whether your amp is class D mono or class AB two channel, the impedance of your combined speakers is still the same.  For the purpose of amplifying subsonic freqs, the class D amp is the most efficient (more than a two channel amp).  The value of that extra efficiency on you car's power supply is greater (for you) than changing amp types so that you can load the amp to its limit.

But if you cannot be happy unless you are loading an amplifier to its limit ("getting your money's worth"), then go ahead and sell those mono amps and buy two 2-channel amps...where you will wire a parallel-wired DVC sub onto each channel at 2 ohms (per channel).