Ambient Occlusion Problems

[BauaMomo]

So I'm trying to make a Better Foliage like resource pack but the grass I added on top of the grass blocks is way too dark.



This probably is because of ambient occlusion being weird, but when I disable it, the grass just becomes black. Also this is not really an option because then ambient occlusion is diabled for the grass block too. Disabling shading also did nothing. So what can I do to solve this? Make a new model just for the grass on top, if yes, how would I get the grass to appear on top of the block?