Arp head studs question

[91stockcoupe]

I know there is a lot of information on this but I am doing a head gasket on my ka and I have a few questions. Is it absolutely necessary to thread in the bolts first before putting on the head or could you line up the head and then thread them though? Just seems like it's easier that way. I've seen a lot of different answers on what to torque them too is their a definite answer to that? I'll be using the arp lube. Also what size is the nut? I think I'm going to need to buy the socket. Thank you.