I hate to bring this up again, but what gasket is good for the Tri-Y headers. I don't know the dimensions of the ports so I'm not sure of the size(headers we're on the car when we bought it). Anybody else have Tri-Y's and have a suggestion for brand??? Thanks and sorry again!
Try Percy's "dead soft aluminum" header gaskets from Summit or Jegs - the holes are a bit undersized so you can open them up to match the ports in your header flanges. Use header bolts and some matching nuts to hold the gaskets in place while you crank up the Dremel tool or die grinder with a carbide bit - the aluminum cuts easily.
Add a set of Stage 8 locking header bolts and you'll be leak-free for a long, long time.
I have had no problems with my standard Fel Pro exhaust manifold/header gasket. I've even had to pull off the header a couple times and reuse the gasket and no leaks.