The B disc has larger tabs and is labeled as 425.

The A disc has 3 notches in the tabs and is labeled as 825A on the tab.

After making sure the damper is aligned with the o, and after the first A,the rest alternate steel plate and clutch disc. All the teeth will have to be aligned when you line up the disc tabs in the clutch basket. The damper plate is the only one you have to align.
Hope this helps