I have been looking up on JBA lately and I am pretty sure that their catted H is only for the mid lengths,I have been looking for a catted H for the stockers and only ones I can find that make a catted h is MRT($519)...for the stock manifolds anyway.JBA considers their mid length headers to be almost LT's but deffinately longer than shorties.I think that Jegs site says what mid pipes fit what by part numbers for the JBA stuff,maybe try cross ref.The BBK's are for 86-93 and Mac isnt making theirs right now.So from my research the last few days its either MRT, or a catted X.