Modding Help Building Shadows Fix?

I'm making a new set of buildings and I just finished houses (1-3). No problem there so far since there was really barely any shadows there. After that, I started working on the on the stable and well... but I'm having problems with the shadows. As you can see on the pic above, I can fix the shadow with the actual building PNG but there's this extension (darker shadow) at the end, attached to pixels I edited. That's where the problem comes from. It looks weird and off...

I unpacked all of the Stardew Valley files and I've been looking where I might find the shadow for the buildings but I can't seem to find it or I might be looking at the wrong place or thing altogether... If anyone can help me fix this up, that'll be awesome.

Just so you know I'm completely new to Modding here so be as basic as possible when it comes to explaining things to me. Thanks in advance~ (^_^)

 

Hi, did you find any solutions?