Do anyone know who Carmine Galante's underboss was

I'm just wondering because if Carmine was the de-facto street boss he had to have a right-hand man, and everything I read on him doesn't talk about it.

Galante basically being the de-facto boss didn't necessarily mean he could install his own underboss, though he very well may have had some right-hand man. I think the official underboss of the family at the time was Nicholas "Nicky Glasses" Marangello.

Marangello was supposedly demoted after the hit on Galante because he was felt to have been too close to the de facto boss.

So my answer to the original question would be Marangello

IMO, Galante was never an official boss, he just assumed the title without the blessing of the family and commission.

He made himself de facto boss.

If anyone was his right hand man, it was one of the Zips. But to call this person an underboss is not correct, IMO.

In his testimony Sal Vitale verified that Galante had never actually been the official boss.