I pulled the old bracket records for an FR5 proposal and found every alignment tick was taken in the jig, while the loose-part failures sit in a separate notebook; before we copy the jig's mystery shim, I'd like to connect those records to actual parts and drawing requirements.
Match the part and fixture revisions first, then have quality define the loose-part measurement from the drawing; the notebook and jig sheet may be checking different features or using different references.
They were using different references, and two fixture revisions are mixed in the folder. Quality has sorted the traceable records into groups. Still no explanation for the shim, so it stays out of the new drawing for now.
Can the original operator explain its purpose? That could guide the investigation, although any remembered correction still needs checking against the current parts and acceptance requirements.