The Y-pipe does fit, I know it is amazing. Considering the fact that I had problems too. At first I thought the flex pipe flange was warped (becasue it would not seal and it sounded like i had no exhaust) so i got a hold of Nick and he sent me another, well it was doing the same thing it turned out the be that I had the wrong size gasket, I then got one from autozone and viola it was sealed and I had some trouble with the 02 sensor holes but i end up going back to the original Y-pipe that he had sent me and it works perfectally with the new gasket.
Well fear not duratec owners me a nick are working on a revised y-pipe. I am sending him my stock y-pipe so that he will have it to take meausurements. Hopefully it will work out and we wont have so much difference between pipes built of the same jig.
Jarod Adams