A904 front pump install problems 63 Dart GT

The "keyed" washers are the ones that go on the planetary sets.
I'm sure you noticed the tabs/keys on them when you put them in.

That 1" or so fiber washer goes between to two shaft end where they meet.
(which I'm sure you have right because it can't go anywhere else.

You may have a planetary washer not seated all the way though, causing the tight clearances.
If I remember right there is one washer that can only go on the planetary set one way and seat all the way against the planetary assembly.