Single 48v power from dual 24v smps

Thanks, that's what I expected but I'd rather be sure before I try it and cause damage.
The reason is that I see a lot of dual smps on chinese marketplaces with very compelling pricetags.
There are some smps's that are sold as single output supplies, but they use the exact same pictures for the ad as the dual ones.

For instance:
dual: Assembled LLC Switch Power Supply Dual DC 24V 36V 48V 50V 500W Power Supply Board For Power Amplifier|Amplifier| - AliExpress
single: 500W HIFI Amplifier Switch LLC Soft Switch High Power Supply Single DC Output 24V 36V 48V 60V 70V 80V Replace RingCow H133|Amplifier| - AliExpress

They even have 3 output terminals.
So that means I should be fine with one of these, but I need to make absolutely sure the board is made for 0 - 48v, and the ground points measure 0. If this isnt true than they just sell dual output boards as single output. In which case I should isolate the 0v output from ground, right?
should -v output then become the new ground?