The new Glues are great stuff , BUT its the clamping that gives it its strength, pretty hard to clamp the center of the hood.

I used to use ( years ago ) a product called KLIX
it was an asbestos like clay that you formed around your weld area that absorbed heat, this was when we had to gas weld everything, before wire feed welders were introduced to the Body Shop Industry.
I think 3M has a product that is like a thin jelly substance that absorbs heat also , I remember the 3M rep comming in the shop around 4 years ago promoting the product.....you could rub it on your hand and wave the torch over your hand and never feel the heat from the flame.
I cant think of the Products name off hand . Might try your local Jobber and see if they have this product.

The reason I gave the wet towel trick is because of the cheap factor, as some of these products are expensive if your only going to use them one time.

Spray