crack in sound board

[tomer6382]

hi
i have upright piano and i found a long crack on my sound board.
i have a few keys that whistle.
the tuner said that the crack cash the whisle.
i didn't want to fix the crack.

how to fix the crack?
i saw 2 types of fix:
1. by putting a wood shims and glue in the cracks.
https://www.rayspiano.com/B-KnabeUpt1907_files/11-KnabeUpt1907BoardCracksShimmed030315.jpg


2. by putting a ribs with drill on the cracks.
https://www.stevespianoservice.com/crack.htm
https://www.stevespianoservice.com/57-sdbd2.htm


which way should i need to use?
how to do it?

thanks
Tomer