Does any one have any experence with ceramic coating exhaust headers on a 308 QV? I removed all the aluminum skins from the front and rear headers. Underneath are some *****n' looking stainless steel tubular headers. A few years ago I had the headers on a blown small block Chevy motor coated and it certainly helped to keep the heat inside the pipes. My question is, should I do both inside and outside or just one surface? Any suggestions?