Linux NFS - set default user for new files on nfs share

I use CentOs as nfs server nad 2 Centos machines as clients. I have some problems with permisions/ownership for new files/directories created from clients on nfs share.

My exports file:

/media/nfsshare *(rw,sync,no_root_squash)

And my idmap.conf:

[Mapping]
Nobody-User = nobody
Nobody-Group = nobody

Finally, fstab on clients:

172.18.2.132:/media/nfsshare /shared-disk nfs rw,addr= 0 0

I set /shared-disk permissions to 777 and all clients can create/delete files on mounted share. But:

• I don't want 777 permissions. I rather need 660


• Every file created by clients has owner: '-2 - user #-2' and group
  '-2'. I want to ownership for user who created file - system users
  for each client has the same ids, groups and group ids.

Any tips?