Craftsman GT6000 - What size bolt for PTO Clutch?

[DPend]

Hi, I've got a Craftsman GT6000 917.288613 and for some reason the main bolt on the PTO Clutch sheared. I manage to get the small remaining piece out, but was wondering if anyone knew the right size and spec replacement bolt? I can't seem to find it in the manual.

Thanks,

Dan