Flip the Drum over.
Replace the 4 Teflon Sealing Rings on the Input/Turbine shaft.
Use the One Piece Sealing Rings ONLY, Use Scarf cut or Step cut at your own risk!!!!
These are difficult to install without Installer & Resizing tools.
There are several DIY methods on the internet/YouTube, Some pointers....
Do not over stretch the Seals, Just enough to go on without damage.
Do not Under Size them either! Using hose clamps & what not, Just get them small enough to lightly rock the Stator shaft on them.
Install the selective shim & Torrington Bearing on the Input Drum, Slide the Stator Shaft down the Input Shaft to do Final Sizing.
Always resize 1 Sealing ring at a time, Start with the Bottom Ring First!
The Stator Shaft is bolted to the Pump Body, Use Pump Body/Stator Shaft assembly for Final Sizing.....Just to be clear.
Another option is taking the Input Drum to a trans shop for Sealing Ring Install.
1st pic, My install tool.
2nd pic, Found on the internet using a Lip Wizard