do it your self. here are the dimensions for both the chevy and ford bolt parttern http://www.jalopyjournal.com/forum/threads/shoebox-flathead-to-t5-adapter-plate.625273/
Last I knew he was still making them. I got mine a couple of years ago from him along with a few other pieces he suggested. Phone number is Dwight Bond Second Chance Cl***ics Gibbon NE. 308-468-5885 When I bought mine he had me send him a post office money order and then he takes the parts to the post office when he gets the money order and kills two birds with one rock. I ended up buying the adapter, pilot bushing and clutch shaft extension from him.