I know it has been said to add a heat shield when adding a header. I have asked some where els but lost it. What would be better fabricating a heat shield to attach over the header or heat wraping the header. there are prose and cons to bouth. The bigest con I can think of with the heat wrap is it will keep the heat in the header, around the ports and even increase internal engine temps. The heat shield would not be as effective as the wrap but would allow heat at the header to dissipate instead of collect and increase.

So what would the best option be as I don't want to cook the side seals and spring but I don't want to cook any thing above or around the header.

 

The OEM heat shield is a layer of shielding bolted close to the header, but not touching. Just replicate that.