Lookin for some headers for the 454 goin into my '83 K20. I've been lookin at the Thorley Tri-Y's. Does anyone here run a set with a big block? Hows the fit? Any installation problems? Any reason to get anything else of comapreable quality? No cheap ass $129 Headman or Flowtech junk. Getting closer and closer to swap time, Just tryin to get all the bases covered.