I finally realized what the problem with my
solenoid replacement from the salvage yard was.

I replaced it and it would click, but would
not let me into 4th gear. After removing and
replacing it a few times to check various things,
I realized that there was some gunk getting sucked
into the smaller hole on the solenoid everytime
I clicked the O/D to allow me 4th gear. I looked
into the solenoid space on the transmission, using
a small mirror and in one of the small holes I saw
this gunk/rubber, which was actually part of the
smaller ring gasket, which had broken away some
time in its life. I got it out and the solenoid
worked fine.....HURRAY.
Joseph