The problem with this is the backface culling isn’t that great and you can still see the edges and vertices of the mesh from the back side which makes it rather difficult to select the geometry.

So I decided to not use “In Front” and to use an addon to keep the retopo mesh above the highpoly, it’s called “Draw XRay” and you can get it from this page:
https://gumroad.com/bartoszstyperek#tWdMQ

After that I retopo the tombstone mesh fully and bake the mesh maps with Substance Painter. Then I add a stylized material which is made by Adam Homoki, you can get it from this page:
https://gumroad.com/a/361477235

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