I can't say anything about the RI, as I have no experience with it. But I would be careful taking him in the bath/shower with you. The water temperature that a normal human likes is far too hot for a snake. It should be just barely warm to the touch. Get a thermometer if you can. Also, I would recommend putting him in a tupperware of sorts with only an inch of water. You can safely leave him in there for quite a while, and it'll help get the upper body shed off.