There is no way to reach a stereo one-ohm load with four 4-ohm speakers. You can achieve a 2-ohm stereo or 4-ohm bridged load which is essentially the same thing.
Plus, there is a difference when running an inordinately low impedance load in an air conditioned hatchback or SUV versus a boat, especially in July and August. So I wouldn't run a one-ohm load regardless.
In any case, based on the rating that amplifier is light for two pair of HLCDs.