I'm not aware of an aluminum bell housing that will bolt to the truck cross member. If you are using the front motor mounts (at the front pulley) you need to also use the bell housing mounts and then let the tranny just hang off the back. Using the bell housing mount will then automatically line everything up so there won't be any clearance issues.
Note, your V8 will need to have the stock (low) valve covers or they will hit the cab fire wall.
I used a clutch kit for a 1980 Camaro, I think it has a 10.5" clutch...feels good to me.
I used a stock truck V8 cast iron truck bell housing with ALL of the stock pedal linkage (Clutch fork, throwout bearing, adjusting bolt, J hook and return spring etc.).
Mike B >)