The confusion might stem from the fact that the current V8 Cadillac lump is a Northstar derivative... in a rwd chassis 
It can't possibly be a Northstar, hence it sticks in my mind that TIS said it was...
...unless my marbles have gone, and I read it somewhere else, not TIS. Thing is, if I read it on Internet, I'd assume it was bullshit 
It might have been, I will check at some point as there is also something in my mind saying the same.
Northstar is not nearly as wide as you think as the stroke is not nearly as long as the Gen IV 's(so the deck height is less). Plus exhaust manifolds are very well contained and dont impact on the width.
They were also built as of around 2000 for rear wheel/four wheel drive apllications (water pump moved etc).
However, the control system is pretty advanced with variable valve timing etc so getting on running outside of is targeted vehicle would be a challenge