Broke down a 15.5 ga Sanke today, full of Labatt's, vintage 2006, re-kegged, brother-in-law will love it (

Yes, I know!).
To the point of my question. This partiular keg had one of those twist thread spears in it with the locking ring that is extremely hard to get out (not the usual split spring rings). Took about an hour to get the thing out and it's not the easiest to put back in.
Question, has anyone used Sanke's for fermentors? A #11 bung fits perfectly in the opening, however, I'm worried about cleaning - especially the underside of the top.
Additionally, has anyone ever modified a Sanke with, say a 6" tri-clamp fitting at the top? Who could do such modifications?
I would hate to make a coffee table out of the thing if I could modify it to make something useful instead.
Cheers,