Yes, I have 2014 Ford E450 3010DS. I bought the swivel from discount van/truck online via their website. I dont know the part #, but I think it was for 96+ Ford chassis. I think it is slightly raised compared to stock, but not much. I sat in the seat and swiveled it to the rear withoit and clearance issues.
I was leery of purchasing from that place because I found bad reviews with the BBB, but couldnt find the swivel base anywhere else for $209. They were all $300+ through other companies