The smoking gun here is....... it was shifting before you took it apart and it’s not shifting after you put it back together. There is no easy fix. You are going to have to pull it back apart at least as far as your original disassembly. Get a copy of the FAM for your particular truck and reassemble very carefully. Good luck.
Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
“I fought the law and the law won" now I are a retired one!
Support those brave men/women who stand the "Thin Blue Line"! Hug a cop!
USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
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