I have modded several V11R’s and V10R’s. The latest mod I did I went with a LH351D 4000k high Cri in a V10R. I sanded down a 16mm Noctigon board I had that uses a xpg size footprint (3535). Several years ago I had already swapped out the led to a Nichia 219b 4500k high Cri and that was what was in it. I gained about 100 lumens just from switching to the LH351D. Produces, in my opinion a very nice beam.
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Might be a option if your interested.
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If you have not cracked open the light yet there is several methods used, you can use the search to find them.
This might also help with the packing grease. Re-packing a V11R