1988 Golf Automatic Transmission question

Hello all and thanks for your help in the past. I have encountered a
new problem and need your help.
I picked up a 1988 Golf with an automatice transmission for a really
good price. It wasn't running, but with your help I got it
running....at least the engine that is. After I fixed the engine, I
put the car in gear...sometimes it would go in gear and sometimes it
wouldn't. After pulling the tranny pan, I found that it was full of
sludge. To keep it simple I decided to find another and swap it out.
I found a tranny with very good clean fluid in it from a 1990 jetta
that was junked because of a blown head gasket. I pulled the tranny
myself and installed it in my car.
I adjusted the linkages according to my Bentley manual. When I try to
put it into gear for the first time and every time after that, it
will not engage into any gear but you can hear a ratcheting sound like
teeth on a gear trying to engage into another gear. I quickly shut it
down. I have checked and re-checked everything that I can think of
but I am stumped. Does anyone have any ideas before I have it towed
to a tranny shop for an estimate?