I have a V8 ED which looks like it has done a head gasket. It drinks coolant very quickly and the oil looks like a milkshake. Started pulling it apart and we ran into a few issues:

1) The spark plugs are all clean, none seem to have any moisture on them. We've removed the intake manifold and it's full of crap. Is it possible for the inlet manifold to have a crack or something in it? Drained the sump and significantly less water/oil mixture came out then I was expecting. The only place I can think of for it to go is out the exhaust, but it seems strange that the plugs are all clean.

2) The motor has been sitting for a while (~4 months) and looks like it's siezed. We wanted to turn it over to TDC but couldn't get it to turn from the flex plate. The clutch fan is getting in the way of getting a decent socket on the harmonic balancer, how is the clutch fan removed? The manual I have says the nut securing the clutch fan to the hub is a right hand thread, so which way does it have to be turned to undo it - drivers side or passenger side?

3) I can refit to the car GT40P heads and an Explorer intake manifold from my brothers AUII XR8. Are these items just a straight swap with the ED motor? Is there any ECU tuning or the like required? I'm not especially after more power but it would be nice especially if the motor is going to be apart anyway, might as well put the good stuff on.

4) I also have a set of EF/EL electric thermofans here. I have a Davies Craig kit to control them. Worth fitting these? Or just get the motor running first?

5) At the moment the car is sitting with intake manifold removed, spark plug holes full of WD40 and sump draining. Next steps was going to be remove clutch fan, remove sump and inspect bearings etc, remove rocker covers and the heads themselves. Sound about right?

Thanks in advance.

It might have leaked coolant through the timing cover into the engine. Thats alot more common than them doing headgaskets.
RH thread is a normal one, so turn it left or counter-clockwise to undo it.