If you upgrade, preserve the original configuration where possible

When modern components are needed for use, favour solutions that avoid permanent alterations when the technical result is still adequate.

Avoid cutting original wiring, enlarging holes or removing mounts if a compatible alternative exists. Keep removed screws, brackets, knobs, components and packaging.

Label everything so it can still be associated with the correct instrument years later.

Retaining the original parts does not make a modified item original, but it preserves options and documentation.