Yes, it's offered on 2011+ Transit Connect models (Van XL, Van XLT, Wagon XLT, Wagon XLT Premium).

It's listed as CNG/LPG GASEOUS ENGINE PREP PKG, order code 90G.

I've seen a few with this option, but not many. Most individuals don't order it, instead you see it more with fleets who order a bunch, and then send them all to get converted by a conversion company.