ZCHondaCRX91

My 88 Civic with auto transmission is making a whine/grind noise when it goes from reverse to neutral or park. If I go from drive/second/neutral straight to park there is no noise, or if I go from another gear into park. It only makes noise if I'm in reverse and shift to park/drive. It's a whine that sounds like a creaking door for a second or two. Fluid level is fine with new fluid. I bought the car and rebuilt the engine so I don't know if it did this before, last owner said everything was fine before. It seems really weird that it only does it from reverse. Transmission mounts are all brand new, and other than that it shifts fine. Anybody know what it could be?

New Information:

I found the shifter linkage where it attaches inside the transmission, the little sleeve feel out when installing so it would slop around. I fixed it and it still has the problem, and I also noticed putting it into drive/reverse it's very jerky and hard. Fluid level is fine, anything else it could be? Are the solenoids on the transmission just for shifting between drive gears while driving? It shifts fine while driving, just when I go from reverse to park or reverse to neutral is sounds like creaking door. Sometimes it will go into the gear fine, but a second later it makes the noise. It doesn't seem to do it after being warmed up, but I'm selling this car and want to fix it before I sell it. Any advice is appreciated.