Michael, if this gun has been apart, the lock plate and the trigger plate housing screw that goes behind the safety could be mixed up, especially if this is a Field Grade because the lock plate screw head would be engraved.
The lock plate connecting screw is longer than the trigger plate screw and this could be your problem. If the tang screw is now the lock plate connecting screw and it is flush on the right side, you are pulling the trigger plate closer to the sear/s.
If you take out those two screws and look closer you will see that the head of the one screw is thicker than the other, and that one is the lock plate connecting screw. The tang screw with the smaller head should be flush with the top tang behind the safety.

Also when I described "timed" it meant that the screw head slots should be in line with the length of the barrels. Trevor's grandfather might have used "timed" in another way.