This worked very well for me using an USB enclosure with and ext3 partition.
Originally Posted by AFarris01
I used pydsm as above, but set the username & group in the section specific to the hdd I have, so that it does not change the mounting of other disks I might connect.
One observation is that after configuration it did not change the permissions right-away, so I did
to get the result I wanted immediately.
sudo chown userX.userX /media/disk
On a subsequent reboot, new kernel image, it mounted with all the right permissions. I think doing and logging out will give the same result for those who don't want to go through a reboot.