I am full of questions tonight.....Anyway, sometimes when I have the clutch all the way depressed and I try to shift into fist, the gearbox grinds. I figured out it does this if the clutch is not fully disengaged. It is easy to not fully disengage the clutch because there is a lump on the floor right next to the clutch pedal on the left (idiot design I think in this instance). So I have been very careful to fully depress the clutch, but it still does the grinding sometimes. What does this mean?

 

Your gear synchos may have been damaged by the grinding.
Be careful to always fully depress the clutch before shifting.

 

when was the last time the clutch was replaced?

my wifes old sentra started doing what you described just before the clutch finally went.............once it was replaced the problem went away.

perhaps you're clutch is just on its way out ?

 

Clutch feels as if there is a lot of life in it, and doesn't slip at all. Still I feared youd say that. I just got the truck and it's allready costing me big bux. Can a home mechanic easily do a clutch or do I need to lay out the big bux?

 

from what you stated it sounds like you may want to look at the clutch master cylinder and slave cylinder .If your clutch is still strong running.
typically the slave will go first and a short while later the master will crap as well.
the slave is easy to over haul very similar to a drum brake cylinder in design. you can check it by going to the driver's side of the tranny and look for the cylinder then gently roll the dust cover back and see if there is fluid in it .another indicator of bad seals in the system would be to look at your master cylinder resivoir if the fluid is dark to black in color the master cylider seals maybe shot .
the master though may have to be replaced as a unit, I'm not positive on that though.
thats the hydro end.
If you have a mechanical set up i.e. cable/linkage it might could be out of adjustment.
Just a coupla avenues and easy enough to check
good luck
Daniel