I bought a 2013 Transit Connect about 2 years ago and I often move large objects in the rear cargo area. I prefer to secure things with ratchet straps and there are very few places to anchor them in these vans. The two D-rings in the rear are useful of course, but there's nothing really anywhere else. Up front I've been anchoring to the seat frames which is awkward. Recently I decided to do something about this and installed a bunch of nice stainless steel lifting eye bolts in the various threaded insert locations. All of the larger threadserts in the cargo area are M10-1.5 thread, including the rear D-rings. I wanted to share some pics of this mod because it's been a huge quality of life upgrade so far.
Stock D-ring:
Stainless lift eye with M10-1.5 thread:
Rear lift eye installed:
Five M10 lift eyes installed, circled in green. One M6 lift eye up front on the B Pillar, circled in blue: