Just a tip for those looking for heat shield material, who have access to a Walmart. I bought the 8 qt version of this:
https://www.walmart.com/ip/Mainstays-Stainless-Steel-8-Quart-Stock-Pot-with-Lid/37320201?selected=true

and made a complete shield for my modified stock Renesis manifold, using about 2/3 of the material. IIRC, the thickness is around 0.016".

I found it to be a good value, based on the sub-$10 cost and local availability.

Charlie