Impossible to move toilet backwards?

Hi there,

I'd really like to remove some boxing and shuffle my toilet backwards since at the moment it's crowding the sink. However, the soil stack connection is on the right hand side so that there would have to be 90 degrees to go backwards, then 180 degrees back.

Is this impossible? Any words of advice would be welcomed!

Photo of the offending area!

 

I wish I was a better technical drawer!!

Here is a quick sketch, I'd like the toilet to move backwards that 30cm of boxing to the windowsill behind?