Thats sounds like an old style bolt.
I just went through the same thing.
There is a tube down inside the main bolt, and the old style slotted rear bolt has a section that goes
down into that tube.
The new hex screws sit on top of the tube.
The only way to get it to work with a 38 spl bolt lift kit is to machine it off or replace the slotted bolt with a hex bolt.
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