Clutch grinding issue

[chevyky]

Im having a problem with my 3 speed (on the column) clutch. 216 V6

When i approach a red stop light, i will drop it into neutral and coast into my stop. Then after Ive been stopped and idling for as long as 4-5 seconds and I want to put it into 1st gear, it will grind... and I have 2 options at this point: 1) let it slowly grind until the grinding stops, then pop it into 1st or 2) shift right into 2nd gear and start from 2nd (which is not optimal, but it will get me moving).

This also seems to be the case for reverse as well.

I have zero problems going from 1-2 or 2-3 or even 3-2. But its when i am at a stop from N to 1 or N to R that it grinds.

Also, after the truck has been running for a while it seems to be even worse of a problem. But I only noticed it getting progressively worse driving it today.

What have i tried?
-Easing off the clutch and shifting = no change

Can anyone please help me diagnose the problem? Thanks