Hope you are not afraid of heights. The secret is to never look UP. Look down all you want. I took down a 32' tower with a good fan and motor a few years ago and set it back up at my ranch. Here's a few tips:
A gin pole is a 4x4 lashed to one of the legs of the tower at the very top. You want to have an eyebolt at the top which extends well above the top of the gearbox. Use this to remove the fan as necessary, tail and gearbox. They are loose at the top so you want them off before the tower comes down. You really need 2 people to get this done. One to attach the hooks and line and the other to run the tackle. A smart move is to use a truck on the ground in case the person below is a lightweight. You may need more rope for that method, though in case you are using more than 1 to 1 on the pulleys. The center of gravity of your empty tower is about 2/3 of the way up the tower. So, if you use a rope to pull the tower from the top, and another rope on your truck to hold the tower back, you can drop the tower in one piece using a slow pull on the tower rope and someone who knows how to drive on the holdback end. If you have some doubts about your abilities in using this method, instead of cutting (better to unbolt) all the legs, just unbolt 1/2 of them and use the remaining ones for hinges. Since its angle iron at the bottom, you will need to saw thru one side of the angle iron to allow it to bend in the ground plane. If it gets away from you, it probably will bend the tower so take it slow. Erecting it all back up is the reverse. A front end loader sure helps a lot to get the lift started. You need to stake the ground legs to prevent them from slipping when you pull. You also need the restraint rope because the tower may carry thru if you pull too fast and it could come down on the pulling side/person/vehicle.
Its really simple but attention to details and doing prep work pays off in the end. Assembling the tower in sections is a slow, painfull and possibly dangerous process. There's just no good place to stand. If you are really good, have the cemented in ground anchors already in place when you put the tower back up. If its for water pumping, you need to get the well dug FIRST so you know it was worth your time. That's my 2 cents. I did it all by myself by controlling the pull and holdback ropes together. I used a ground pulley to run a return line back to me.
The only real trouble I had was the outside temperature. It was -20 below windchill when I climbed the tower to put the fan on the gearbox. I used my beard to hold the fan bolts while I fumbled at getting them in the driveshaft hub 1 at a time.
She's still standing !!!
. Bob