Updated Magnetic variation data
The Updated Magnetic Variation data package provides an updated set of Magdec.bgl files (2024) for FS9, FSX, P3D (all versions) and MSFS. New values have been calculated according to the exact WMM2020 mathematical model at epox 1/1/2024. Replacing the default MAGDEC.BGL file with the one provided will result in a better fit between displayed headings and current data. A test/information program (Sim MagVar Calculator) is also included. Documentation and install instructions are available here. Historical data are also available if needed (FSX,P3D,MSFS)
EasyNavs
Airport Inspector and Editor (AIE) - BGL Navaids Direct Editor
EasyNavs is an utility that can extract VOR and NDB data from any FS9, FSX and P3D BGL file (with associated scenery objects), edit and save data (via a dedicated database manager) and rebuild updated XML/BGL files.
Airport Inspector and Editor (AIE) is an utility that can extract and edit many airport data from any FS9, FSX and  P3Dv1-v6 BGL file or folder at BGL level without any need for decompiling. Editable data are: ILSs, terminal NDBs, markers, airport ICAO Id, magnetic variation, name and city, runway identifiers, taxiway signs, runway lights, VASIs and runway marks, sim start positions, COM data. For ILS/NDB edition, an up to date AIRAC database is provided.

BGL Navaids Direct Editor (FS9-FSX-P3Dv1-v5) is another program that can be used for editing VORs and NDBs inside BGL files. Version 4.x is fully compatible with P3Dv5. 
Downloads
Updated Magvar data
Documentation
Magnetic variation use
Historical data (1900-2020)

EasyNavs v9.32
Revision history

AIE v3.15
Revision history
Editing ILS tutorial
Renumbering runways tutorial

BGL Navaids Editor v4.10


VOR/NDB table
ILS table
Navaids tools