Yep gotta get tti s

From what I remember, the TTIs were not that difficult to install. Just time-consumung. Ive had mine on/off many times. My 68 S-clone hit the road in 99.Every fall for the first 4 years, I would pull the 366/4spd and the 4.30s, and swap in a 318/904 with 3.23s or less chunk.Then May-long weekend, the 360stuff went back in.The TTIs went from one to the other.Sometimes I would pull it out from the top, other times out the bottom. Then one day my son needed a motor, and made me an offer I couldnt refuse. Its been a 360 ever since.
Back to the TTIs; The first time in, one pipe needed some "adjustments". It didnt take me long to buy a mini-starter tho. I dont have nearly the power that you do though, and she 60fts about 1.9 with the 325/50-15DRs.Still manages 93/in 1/8th. Shes been my summer DD for many years.
If you can manage to keep the X-pipe, thats a definite torque maker. I had to sacrifice it to install a GearVendor. I could really feel the Loss. Took me the rest of the summer to get most/some of it back with tuning. The hole was off-idle to about 3000 or so. Your application might not need it,IDK.Youll like those tubes, for sure.