Lots of dirt to haul away. Bought trailer in lieu of wheelbarrow.
At end of day - 4.5 cubic yards removed. Hole is now 5ft x 5ft x 4.5ft deep.
Build forms for concrete and support tower and legs so legs are suspended in hole. Adjust forms for rain runoff. Shim tower support for perfect tower level.
Check level at least 30 times! Not pictured is rebar cage made of 16 48" rebar rods with none touching any part of tower or legs.
Concrete delivery - 4.5 cu. yards fills hole. Make sure tower stays perfectly level! Trowel smoothe. Concrete sets 4 days.