Try POR-15 manifold dressing it works awesome. I did mine almost 2 years ago and they still look great. The 8oz can is more than enough. Sand blast and prep sol then brush it on.
POR-15 High Temp High Heat Resistant Paint
If you don't have the best mating surface these gaskets are very forgiving and seal excellent. I used them and worked great.
MOPAR Header/Exhaust Manifold Gasket