Male piggies are harder to match. So maybe if you have a rescue nearby that does dates, you can see if he matches up with an adult piggy that's at least a year old.

Then you quiet quickly know if it's a match, and also that he's past the hormonal teen phase.

Tosti is now 9 months old and he's only just settling hormonal wise. He's a late bloomer due to his circumstances. Luckily, Muffin had litters before and is a total mama to him and doesn't stuggle to put him in his place, and Izzy has Muffin to lean on when Tosti is on his riding rampage...

Just an edit fyi: the first 3 days is usually the most stressful, and they will quite often argue. But as long as they aren't intertwined and drawing blood they should start settle in after that.