Thanks.. great reading. I think I'm gonna go sponge bob square pants.This gives a very good summary of the pros and cons of a square v staggered setup (it's swings and roundabouts)
https://www.tirebuyer.com/education/staggered-vs-square-tire-wheel-setups
Actually it's 305/30/20 rear and (IIRC) 285/35/20 front.^^
That's 255/35/20 front and 285/35/20 rear. The most sensible setup for a GT if you ask me.