when did for change the exhaust slightly on the 5.0's

[kovacs32]

So if my research and mind serves me right, ford used a slip fit and flange style muffler to connect to the back of the rear cats on early build 98's and prior. Then, in later 98 models they switched over to a Ball/socket and slip connect style muffler inlets to mate to the rear of the cats. Can anyone confirm this for me? because i am getting a KILLER deal ona mac catback for the 99-01 5.0's, but my late build 98 has the ball/socket and slip connect like pictured in the 99-01 catback pics.

Thanks!
Ryan