When my transmission is cold it shifts but won't when it gets warm

I have same problem with my 2002 gmc 2.2L manual 5 speed. Bought used transmission and new pilot bushing and same problem still. I haven't took transmission out yet but leaning toward cracked clutch plate which I installed New month prior. My problem occurred between parking truck to the next time driving the truck. Gonna try to take out starter and use inspection camera.