best practice when using removable drives and USB enclosure?

I have a four drive USB enclosure that is populated with two drives
currently in RAID1 (md1).  [pay no attention to md0]

mdadm.conf
DEVICE  /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1 /dev/sdg1 /dev/sdh1
ARRAY   /dev/md0 level=raid5 num-devices=4
UUID=cdaba8bd:80943c6a:ab2fedca:3ef56cfb
devices=/dev/sdb1,/dev/sdc1,/dev/sdd1,/dev/sde1
ARRAY   /dev/md1 level=raid1 num-devices=2
UUID=649526d8:828a57b4:ab2fedca:3ef56cfb devices=/dev/sdg1,/dev/sdh1

fstab
/dev/md0                /mnt/teradata           ext3    defaults       1 2
/dev/md1                /mnt/mirror             ext3    defaults        1 2


[Fri Oct 16-22:34:15] [tbostrom@teraserver ~]$ sudo mdadm --detail
--scan /dev/md1
/dev/md1:
        Version : 0.90
  Creation Time : Wed Oct 14 09:38:10 2009
     Raid Level : raid1
     Array Size : 1465135936 (1397.26 GiB 1500.30 GB)
  Used Dev Size : 1465135936 (1397.26 GiB 1500.30 GB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 1
    Persistence : Superblock is persistent

    Update Time : Fri Oct 16 08:11:05 2009
          State : clean
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0

           UUID : 649526d8:828a57b4:ab2fedca:3ef56cfb (local to host
teraserver.teambostrom.com)
         Events : 0.36

    Number   Major   Minor   RaidDevice State
       0       8       97        0      active sync   /dev/sdg1
       1       8      113        1      active sync   /dev/sdh1


When I created the array, I had another a third drive in the enclosure
I was using for other work and the drive letters for the two RAID1
drives were /dev/sdh1 and /dev/sdi1.  After I removed the disks and
rebooted, the array drives changed to /dev/sdg1 and /dev/sdh1.  I then
fixed my mdadm.conf and fstab to list the correct partitions.

SO..... I don't anticipate changing drives in and out of the last two
open slots of my USB enclosure, but what would be the best practice
for making sure md1 comes up at boot all the time without having to
manually go into mdadm.conf and modify it back to /dev/sdh1 and
/dev/sdi1 when I put a drive in the open drive slots?

I'm sure I'm missing some newbie Linux feature and this may not have
to do with RAID.  Any ideas?

Thank you.

-- 
-Tim