Finding good heat shields might prove to be something of a snipe hunt as they do seem to be built to commit suicide. Those cute little screws that hold the shields must be rusty from the factory, I never did get all of them to come out of the exhaust manifolds on my 5.3. I think I broke as many as actually did unscrew. As for the shields, they finally went to the scrap yard this fall. Price of scrap was lousy but I had too much absolute junk strewn about in pails and pans so it all go consolidated and disposed of. I did manage to get rid of the remaining stumps through the simple expedient of taking my air die grinder motor and using a couple of bits to whittle down and smooth out the lumps and bumps on the stockers. Doesn't help the flow much but does make it easier to handle them without coming away with lacerated fingers.
Nick
Nick