In reply to admackie:
Left eliminate, my mate told me i couldn't use anything bigger than a size 4 friend as it would be cheating as he hadn't (though he didn't do it clean!), a larger size would have been nice but might have just got in the way and it was plenty safe enough without.
On Sorrels Sorrow i didn't use anything larger than a size 3.5, I seem to remember there being no real need again for anything bigger.
Elder crack i used a camalot 4 (i think it wasn't the biggest one) that only just touched the sides on the crux but there is a excellent wire just below which would still make it safe. I didn't have anything else left after that (i couldn't quite get a size 4 friend to fit but a 5 i think would) so just one big run out to the top, much easier but not totally straight forward so I made sure not to fall off.
another wide crack to try at Curbar is Hercules, i used a size 6 friend on this, but you could lasso the cock stone early and do it without.
The other obvious one is right eliminate but I've not tried this yet so can't help.
Personally I go for the largest size as it will be of use on other large cracks in the peak (cave crack, the mangler, centaur - not tried this yet)