Gear Grind?

this is probably a no-brainer but, my 88 5.0 is getting some grind going from 1st to 2nd gear. transmission shop wants to charge $900 to rebuild old T5. does anyone know if this is somthing that can be adjusted in the synchros or is the T5 is junked? and if tranny is in need of rebuild, who would pay $900 to rebuild when you can buy a new one for around $1200? is T5 worth the bother or should I spend some extra $ for something more stout? thanks for help!!  

This may sound a little strange but bear with me.  If you are running Dexron oil in it I have been told that this is simply too thin and causes it to grind now and then.  My old tranny did the exact same thing until I mixed 80-90 with Dexron in a 50/50 mix.  If you use 80-90 only it won't shift.  As for the technical explanation I only understand that it needs slight thicker oil.  I was also told that this was a common reason for a trip to a dealer and this exact fix was used in dealerships.    However my new tranny (the old one lost 3rd gear not second if your wondering) runs great and I have mixed synthetic oil in it currently.  Try it before the rebuild.

thanks for advice. i will try 50/50 mix of 80-90 and Dexron. i noticed today that the grommet around speedo cable is leaking slightly. i'm sure this doesn't help my situation. thanks again.