From the Haynes manual :
First fit the type B friction plate, (which is thicker and has the larger internal diameter) so it fits over the anti-judder spring & seat. Now fit a plain plate, followed by a blue colour coded type A friction plate, then alternate plain and friction plates, fitting the two remaining blue-coded friction plates, then the four black-coded type A friction plates.
Hope that helps.
Btw, Haynes manual is a decent investment. Less than £20 on ebay…..