Tim37chevy

I recently had my tranny apart looked okay but now 2nd grinds real bad unless I wait for the engine to slow down then engage gear I was told it was the blocker ring gone bad can I just replace that one and fix the problem or what is it possible a shim was miss placed when I put it back together but that wouldn't make sense cause then i'd have problems all together right? I did have to replace 5th gear cause I chipped it now the tranny whines. In all gears