May need advice on 727 build

you really shouldnt mix parts. they may look the same, but there not. that said, i have see builders put the wide bushing in the narrow drum, but you have to watch that its down far enough so the washer between the drums dosent touch it and that when you place the drum on the stator it dosent bottom out against the ringland before the drum hits the pump washer. clear as mud huh?