I think these videos are at least entertaining, but possibly could be useful for someone:
How To: Resurface (EJ25/Subaru) Heads At Home https://www.youtube.com/watch?v=iC4kmmCy6YM
I Rebuilt my EJ255 for 500$... Forester XT https://www.youtube.com/watch?v=rzrazMO1cmo
The tool mentioned in the second video is https://time-serts.com/store/big-sert-oversized-universal-m11x125-head-bolt-pn-11125bs/