When I took the head off of my Tree for moving I drained the oil first (you will want to do all of the oil changes anyhow) and then flipped it all the way upside down. This puts the heavy end at the bottom for best possible stability. Put an eye bolt in the chuck and lifted it with the shop crane, moved it with a furniture dolly, I think it is under 300 lbs. Just make sure that you have the collet nice and tight on the drill chuck shank, and the drill chuck shank nice and tight in the drill chuck, and the drill chuck nice and tight on the eye bolt. You do not really have to take the head all the way off, You just need to pull it out far enough to change the bolt. You may be able to just set the head upside down on the table, by raising or lowering the knee, and then use the Y axis to move the head out from the machine. I would put a couple of ratchet straps to make sure the head can not tip off the table.
The bolts have a square head made to work in the curved T slot. You might have to make or modify a bolt once you see the head.
To rotate the head, loosen the 4 bolts, (In your case 3) there is a 1/2 square shaft sticking out the top of the ram that is a gear drive for rotating the head. The nod drive on my machine has 2 broken gear teeth (before it was mine) and it is a lot less weight, so I am not sure that the gear teeth can handle the full weight of the head when it gets way out there. I always use my hand to help support the weight while moving it, especially when going back up.
I have been able to find Tree manuals on ebay.