Is there anything I need to do to this sealed unit before I reinstall?
If the bottom bracket is in good condition, then no. If it does not spin smoothly, then you might as well replace it now that you have removed it. (An excellent Made in Japan Tange Seiki BB is only $30:
Tange LN-3922 Square Taper Bottom Bracket – The Bikesmiths, and can often be found even cheaper on eBay.) Otherwise, you may ding the nice new paint job you are about to put on the bike if you have to replace the bottom bracket in the future.