How to change which blender unity uses to export

I have been trying to mod a game that requires me to use Unity 5.6.7f1 and has a lot of assets that are .blend files. I have Blender 2.82 and it continued with the error "Blender could not convert the .blend file to FBX file." and when I downloaded Blender 2.79 and moved the new version out of the folder and changed the name of the old one to match the new one it worked and unity could convert. How do you change where unity accesses so i can redirect it to the old one so i can have the new one for modelling usage and the old one for exporting to unity?

 

Anyone have a answer?