Bob J wrote:

...Another hint I would give is to fill the cooling system with distilled water. When first seating these long heads you will likely get a few leaks until you have retorqued a few times through the heat and cooling cycle. The water will cause less harm than an anti-freeze mix if it gets into cylinder walls and valve seats and guides. Once everything is sealed, drain and mix up your preferred anti-freeze coolant.
Good luck!
Bob J.