That my boy was a lot easier than you thought it was going to be. Always be a pessimist until the job is done, then you feel super happy after it all goes so easily.
Because of it's larger size, maybe semi industrial, mine came ready to go except for a light sticky oil on the table. No dragon grease, no swarf anywhere, gibs set up perfectly etc etc. In fact, I still haven't adjusted the jibs, even after 2.5 years. I just keep it slightly over lubed and it has taken care of itself.
One thing I have noticed, you have the same sort of spindle brake on the head.
On mine, The chuck guard had an interlock switch that was a real PITA. while machining with the guard in position, any slight movement of the guard switched the machine off. I know it is against all safety rules, but I repositioned the interlock switch so that it was operated by the brake handle's first movement, before the brake came on. That way, as you press the handle, power is switched off to the motor first then you apply the brake all in one easy movement. Chester UK started to do that on their new 836 machines after I showed it on their website, they now have two switches, one on the guard and one on the brake. Maybe you could emulate that.
Once you get the head upright, then you can make the decision if you still want it up on dunnage or not. As I said, the spindle brake and controls, for me, were perfect with the machine on the floor. I use a high stool that puts my body in the same position as if I am standing, so that is how I wanted my machine to be. Maybe you would prefer the higher reach.
Because you haven't had a mill before, I don't suppose you will notice the difference between a small benchtop job and the one you have. With everything being so rigid, most of your cutting will be as smooth as silk and you will get great surface finishes, whereas on smaller machines, you really have to work hard to obtain the same effect.
As for your DRO, read up as best as you can on it, and go thru all it's little features, trying them out a few times until you get the hang of them. It isn't just there to show where you are, those extra features really do make machining certain things a lot easier. The PCD function especially, as you can plonk a ring of holes down, any size and number of holes (within reason) perfectly, wherever you want them.
So what is to be done.
First off, get the head upright and decide if you want it on the floor or not. See if you can extract the drawbar completely in the position it is going in, I can't, my ceiling is too low, I have to tilt the head to get the drawbar out.
Move it to it's final resting place, and do a basic levelling exercise, it will stop your coffee and tools sliding off the table, plus it will also stop flood coolant from pouring off the edge of the table
Then go over it with a fine tooth comb to see if any bolts are loose or missing and everything feels the way it should. Give it a good lube and adjust the gibs for your 'feel' if needs be.
Once you are happy with it where it is and what it feels like, start to get your bits onto it. Then it is playtime.
Later on, after you get used to it, can you look at fitting a cheapo scale on the quill to give you accurate drilling depths, power feeds if needed etc etc.
Just as a point of interest, I myself, and a lot of other people as well, when going to this size of machine mount both the vice and RT on the table at the same time. That works out rather well as it saves having to take off and on all the time, and they are always ready to use.
I hope you really enjoy your new aquisition.
John
BTW, I don't understand about the quill and knee handles, on mine they are two completely different shapes and sizes, so aren't interchangeable. Maybe one is hiding inside the electrical box.