In the car you should be prepared for 29V voltage spikes when engine is running and a battery is charged. Maybe you can put two standard (not a Schottky/fast series) diodes (opening @0.7V) in series with (+) wire (let others speak). This amp should survive 27V continuous, but by replacing internal components it can go to the maximum supported by TPA3250 chip, I saw tweaks on diyAudio.
FX-Audio FX502S PRO without PSU.
The price increased recently, from Aliexpress you can get it for $55
FX Audio FX502S PRO Audio Digital High Power Amplifier HIFI 2.0 Stereo Home Professional Amp TPA3250 NE5532 80W *2 Amplifiers-in Amplifier from Consumer Electronics on AliExpress
On ebay I see it for about GBP30, this one is without original factory certificate, but there are more:
FX502A PRO Pure Digital Audio High-power Mini Home Hifi Amplifier 50Wx2 #2 | eBay
Alternative - there are many TPA325x boards that will work in a car without tweaking. TPA3250 is optimised for low voltage operation, I think you get most of power from this chip, it is why I pointed out to FX Audio,
Generally sound quality of TPA325x is better than tpa3116d2, but implementation matters.