Nice! I forgot all about the fact that when I did the job, I replaced the PCV valve and also replaced that grommet since it had a really loose fit just like you mentioned. You may want to do that sometime and get rid of the duct tape just to be on the safe side. The rubber grommet is available as Dorman part # 42049 and it costs a whole 2 bucks.
The PCV valve will fit a LOT more snug like you would expect with a new grommet.
I'd also just throw in a new PCV valve if yours is original. It's $8.62 on rockauto for the motorcraft one. (DON'T use an off-brand or the flow won't be exactly right and it may set the code all over again. At that price, I wouldn't even take the chance.)
PCV Valve:
http://www.rockauto.com/catalog/rafr...&parttype=5052
Grommet:
http://www.rockauto.com/catalog/rafr...parttype=11785