How do I line up timming belt marks on my 1987 Subaru 1.8 sw

On the top of the bell housing is a rubber plug pull it out, turn engine till " III " marks align with pointer
(NOT TDC) install the 1st belt with the dots on the pulleys pointing up, rotate engine 360 degrees back to "III" marks, rotate other cam till dot on gear is down then install 2nd belt release and retighten both tensioners.
At this point it pays to move everything out of the way and start the engine just long enough to see if it runs right, If not remove last belt rotate cam 180
and reinstall belt try running again.
When right reassemble