You might not have to reinstall the MD - try it first, and if it doesn't work, then it's no loss. Or try rebuilding the image with the card installed if that doesn't work.
If you need to reinstall the MD, bear in mind that in the past, possy has recommended that you do not delete MDs, and that instead you should change the MAC address and then the MD will be detected again as a new one. Of course this will leave unused MDs laying around in web admin, but it doesn't matter.
And get clonezilla in your life, stop living in fear
http://clonezilla.org/Cheers,
Matt.