The total cost to me for the rear wheel well liners was 193.28 euros, which included 67,23 euro for delivery and 126.05 for the liners themselves. They came supplied with eight steel sheet metal screws but no specific Ford Transit installation instructions. There is a generic set of installation instructions for liners on their website.
I elected not to install to the rear wheel well with the sheet metal screws, but instead with stainless steel 1/4 -20 threaded fasteners, at the locations shown in the photos. My fasteners were stainless steel hex head bolts 1/2 or 3/4 inch long, fender washers, and hex jam nuts and hex acorn nuts.
Only the top center fastener goes through the Ford van sheet metal with nut on the vehicle inside wheel well liner, and is snugged down tightly; the other three fasteners on each side attach the Lokari liner to the Ford OEM plastic wheel well trim. I used the the combination of the jam nut and acorn nut to attach the plastic pieces without cinching these pieces tightly to each other, thinking that I wanted to allow some slight slippage between the pieces to possibly accommodate plastic expansion and contraction thereby avoiding resulting deformations if it were cinched.
The liners fit well to the curvature of the Ford rear wheel trim, but I needed to test fit several times and choose the fastener locations thoughtfully in order to properly achieve that. The liners have held up well since installed in March 2017. There is no impingement with the tire chains I have used occasionally in the winters here in the northeast.
I have not removed the liners since first installed, so I do not really know if dirt and debris is accumulating between the liner and the wheel well sheet metal. I am hoping that the undercarriage wash I get at the local automated car wash every couple weeks during the winter months is flushing out anything that might get accumulated there.