Tranny ?

With the Clutch depressed grinds going into second sometimes doesn't go in at all. If you push right to the floor it will go in but still grinds a bit. Clutch or tranny

The clutch is easy enough to check so go with checking the linkage and the play in the linkage first. It may be that simple.

But usually it's teh syncronizers that go bad. It's part of the tranny. The 2nd gear syncro is prone to going bad in the T-5. Only way to fix is rebuild. The part is cheap but the labor is going to hurt.

I'm not a tranny repairmen by any means, but from memory... If it's in your Mustang, it's likely the synchro's or the "shift dogs" or bent forks. There's no linkage to deal with, since it's got a manual clutch cable connecting to the shift fork.

There's a small chance the clutch is that worn, but it isn't generally the cause. That said, if you pull the trans and have it rebuilt or replaced with another, get a new clutch kit and have your flywheel turned or replaced as well.

I'm not a tranny repairmen by any means, but from memory... If it's in your Mustang, it's likely the synchro's or the "shift dogs" or bent forks. There's no linkage to deal with, since it's got a manual clutch cable connecting to the shift fork.

There's a small chance the clutch is that worn, but it isn't generally the cause. That said, if you pull the trans and have it rebuilt or replaced with another, get a new clutch kit and have your flywheel turned or replaced as well.
It started last year after I did an awesome burnout.