You might want to try this plumbing code site they have the requirements for a lot of situations. Not sure what you mean that the toilet is wet vented because in a sense most toilets are wet vented. Maybe I didn't understand your description. The stack usually is the vent for the toilet. Sounds like your actually moving the toilet closer to the stack so that's even better. There's lots of professionals on this bulletin board that could answer your question better than I could but thought I'd try since you didn't have any responses.