Even though they don't have any cars with Ford 460's in them, that would be a blast to bore out, then stroke it.
That '71 Mach 1 Mustang has a 351W in it and I'd love to see that bored out 30 over or even 60 over. Then mod the crap out of that in-game, that probably put it at around 800HP if not slightly more,
Since most 351W blocks can't handle more than 60 over the displacement changes would have to be capped there. Meaning the displacement would be around 363c.i. Not sure if your aware, but every 30 thousanths you shave off increases the displacement by about 6 c.i.
Getting a '69 Camaro to go to 383c.i. would be a pain though (if even safe) because a 289 is a smaller block than a 351W and a 351W can only go up to 363c.i. So that means there is less meat to shave off a smaller block which says that you can't go over 350 c.i when you bore it 60 over. Not sure though, I've heard about blocks going up to 120 over. (Maybe those weren't 289's?) Pretty sure 289's can't go over 350 c.i.d. without having problems. If you managed to get it that high you'd most likely end up blowing a hole in teh block.
Would also be nice to stroke it and change the compression ratios.