What to do with this Schlong cactus?
So... I'm not really a big fan of Cacti. I've had this one for at least 5 years and it was initially only about 1.5" tall. Despite serious neglect, multiple moves and a couple near death experiences it continues to come back and it has bloomed within the last year. I finally acquired a house and I think he has earned his stay. Clearly needs repotting, but what's the proper way to do so in this case? Any suggestions are greatly appreciated.
Light: Currently next to an East facing sliding door. ~3 hours direct light and lots of bright indirect light. Can certainly be moved. Have a large deck outside if that's better.
Water: Every time it dries out completely, which is frequent due to the tiny dinkus idiot pot.
Bonus: Can I transfer the other cactus into the same pot as the schlong or nah?