2nd gear grinding

It could be a number of things:

1-The leather shifter boot might be getting bunched up down by the shifter base
2-Or your clutch quadrant can be mis-adjusted, or the mechanism might be broken
3-Your syncros could be on the way out
4-You might need a simlple fluid change
5-Bad clutch fork
6-Driver Mod

Id start with 1,2,6,&4

check the amount of free play you have at the bottom of the clutch pedal.

you should be able to put your foot to the floor on the clutch, put the car in first get and lift your foot off the clutch 1-2 inches before the car starts to inch forward or the RPM's start to drop.

If you can not do this there is 2 things you can do...

1. buy a aftermarket quadarant and cable adjuster

2. you can mess with the stock quadrant manually pulling the cable a click or two tighter.. I do not feel like explaining this in detail, but if you do a search you will find the step by step instructions on it.

this is a very common problem in our cars.. In fact many of my customers mustangs I can hardly drive because you need to put your foot thru the floor to get the clutch to disengage.

Now also remember more air gap is needed for a clean shift at higher rpm's So I would adjust it so your closer to 2 inches of travel

I had that same problem with the 2nd gear grinding in
my 96 GT one thousand miles after I bought it.I took
it to my mechanic.He took the T-45 apart and it turned
out that my throwout bearing was ruined and my shift
fork was bent also.I had him replace those parts and
put some Royal Purple transmission fluid in.My T-45 transmission was running perfect after that and I never
grinded 2nd gear again after that.The owner before me
couldn't drive stick obviously.Mike is correct I would get
a aftermarket quadarant and cable adjuster they are worth their weight in gold lol.