Hey, thank you for rescuing the guinea pig, that’s super lovely of you! I have owned guinea pigs but it was a very long time ago, as child, and although I’ve learnt some things on tumblr, I don’t really feel I can verify what is good information and what isn’t so I think it’s best if someone else with more experience answers this, rather than me throwing possibly helpful links at you or something.
But many of my followers have guinea pigs so please consider signal boosting or answering this question if you know about guinea pig stress management and preparation. Thank you! :)
(Good luck and sorry I can’t be of more help.)