I have had two 3 speed AD trannies in my trucks and they were both good. However one had a bad synchro ring and it made shifting up a bit noisy unless I double clutched. I think if the parts are good and you check and replace the bearings if necessary you should be okay. Parts are available. On the other hand depending on what you have and what you want to do with it, there are other manual transmission options.

1949 Chevy 1/2-Ton
"Sedgewick"
In the Gallery
1989 Caprice