I understand that sandblasting is the best preparation for Hi-Temp, but if I wire wheel the surface, then use AquaKlean, should I then use RustBlast before I apply the Hi-Temp? I was not sure if the RustBlast could be used because of the high temperatures.

Yes, you can use RustBlast (http://www.kbs-coatings.com/rustblast.html) before applying Hi-Temp (http://www.kbs-coatings.com/hi-temp.html)to prepare and etch the surface. We always recommend scrubbing the RustBlast with a coarse scotch brite pad to prevent excess zinc phosphate build-up which is purposely left behind by the RustBlast. In High Temperatures applications, it is best to have a minimal amount of zinc phosphate left behind by the RustBlast.

Here is a tip: If you are trying to prevent rust on your high temperature application (like headers, manifolds, exhausts, smokers, stoves, grills, etc.), apply a coat of Hi-Temp Zinc Primer (http://www.kbs-coatings.com/hi-temp-primer.html) before the Hi-Temp for the best high temperature rust protection.