which long tubes for slp x-pipe?

I recently installed the multiple piece SLP X-pipe. From my understanding, the cats and front pipes are just clamped on and supposedly ( the text on the website selling the product ) said it can be used later on down the road with no cats and long tubes should i go that route. So thats why I got the SLP, so incase I kept modding I would be safe. However, I bit the gun too soon and forgot that the headers would have to mate too. I was wondering which LTs work for the SLP X-pipe and an auto? Thanks! I really hope flowtechs do cause I read hookers do and flowtechs are based off hookers? I dunno but I look forward to you guys' input.

Tim

well the whole transmission blockage thing, i plan on getting the j-mod, tranny cool done after the LTs and removing a header seems like a lot of work and extra labor $$$. Even with some custom cutting and what not on the pipe from my muffler shop?