Roman Tub Spout Leaking

Hope someone can point me in the right direction. I have a deck mounted roman tub slide on spout from Moen. Problem is the water supply shank coming up through the deck is to short to pass through the rubber O-ring. Is there anyway to extend the shank without replacing the inverter assembly below the tub?

Any guidance would greatly be appreciated.

Thanks,
Bill

Hi Bill,

I was just curious as to whether or not you were able to fix this problem. I am having a similar issue and not quite sure what to do. Any suggestions are very welcomed!

Thank you,
Tammy