Tranny Grinds on Shifting into Reverse

[Berkeley and Bill Conner]

I recently put a CAP HP clutch and Fidanza flywheel in my 1993 SE-R.
All seemed to be in order until I spent a little more time driving the
car.  Here is what I have come to notice:

When the car is cold, everything works just fine.  She shifts like budda
-- including into reverse.

Once I drive for three quarters of an hour or so, she grinds when I
shift into reverse.  I make sure the car is absolutely stopped, depress
the clutch all the way to the floor, wait a few seconds, and shift into
reverse.  She grinds.  Every time.  Ouch.

This only happens after everything gets heated up.  I can drive for 15
minutes -- still like budda.  Forty-five minutes, and she grinds.

FWIW, I am running fresh MT-90.  And I don't think I had this symptom
before I changed the clutch.

Any thoughts would be appreciated.  I can reduce the "slack" in the
cable to see what happens, but it's pretty tight already and I don't
want to pre load the TO bearing.  Maybe once the disc wears in a little
more, the problem will be reduced?

Thanks in advance.

Bill Conner