[Samba] Information needed,, wide open to ideas.. ACL's

[Aaron E.]

I'm looking to migrate to samba4 AD domain from samba3 but this will not 
happen over night, I plan on slowly migrating which brings me to acl 
issues,

I will be creating a new domain but still need to have a single data store.

IS this something that can just have a domain trust built?

Can I somehow mount the data on the new domain and stay relatively close 
to the acls that are currently in place?

NFS, smbfs? I'm hoping for some direction or best practice in a scenario 
like this..

Give me possible items to research, possible scenarios etc..

I am completely open to ideas.

Thanks you
Aaron