In case you missed it I said 9" was standard, your truck could have been ordered with the HD clutch.
I for one use the smallest disc on most jobs. The reason is, in my experience the larger the disc the more chance you will get clutch chatter and it is easier for the synchro's to bring to speed.
Now that is something new, I'd never heard... I had always figured to go with the larger clutch. I have flywheels for both......
John
