Looking for a strong narrow version that will work with the shock in place for increasing and decreasing preload. Either direction, the tank still looks like it has to be raised.

I have a few here, and the Motion Pro spanner accommodated a removing of preload, but not increasing preload until I darn-near removed the shock. If nothing else, maybe a few minutes at the grinder will help.

Maybe the one in the tool kit if the wrench portions were cut off.

Definitely a good call there @mcrider!

If I need more information, can you suggest where I should find it?