Rear drum tight... Wrong brakes or axles?

Just swaped an 8 1/4 to 8 3/4.
Bought the housing and axles separate. Anybody know why the drums bottom out before they seat on the axle? It's causing them to lock up.

(Pic reference) Where the red arrows are there is about a 1/8" - 1/4" gab between the axle and drum. They are bottoming out where the backing plate an drum groove are. (Green)

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