Flywheel ? for the /6 guys

There was a bigger bellhousing on trucks that I believe worked with/6 or small block but that flywheel was much bigger.
That bell housing was used with the NP435 (I think that is the number) trans. That is the 4 speed that has the shifter go right into the top of the trans, with a "granny" 1st gear. But I don't believe it has a dual engine bolt pattern. I have that flywheel and clutch on hand, but no bell housing. The flywheel has the slant bolt pattern.