Help With Binding to 10.6.8 Server

Hello everyone,

I am new to Server, and was hoping someone could help me out. My company has about 50 macs or so. We have a 10.6.8 Server that is primarily used for AFP file sharing. The users authenticate to the server only for AFP shares. They are not bound to the server. What I would like to do is, bind all the machines to the server, use there already set up user accounts (that they use for AFP) and switch their client machines to login and authenticate against the already set up accounts on the server. I want to keep their home user folders local on their machine. The server is set up as an OD Master. I was able to successfully bind a machine to the server, but that was as far as I got. I could not figure out how to get the machine to authenticate against the server while keeping their current local home directory in tact. Most of the clients are on 10.7. Any help is greatly appreciated! Thanks.