Well...the answer depends on exactly what parts you will be replacing. The job is not "hard"; but it is time consuming and the potential to get yourself hung in the middle of the project because you did not anticipate something or dont have ALL of the correct tools. Also, 3" will almost guarantee the need for UCA's to get the steering geometry back to close the the stock settings.
I am currently waiting on Eibach to finish the TRD PRO front coils, but here is a mostly complete list of what I have available for the project.
Coil spring compressor, ball joint separator, 24" x 1/2 breaker bar. A complete set of METRIC wrenches 5mm-30mm; A complete set of metric sockets in 3/8 & 1/2 drive. 5-32mm. A small air impact wrench with selected metric impact sockets 15,17,19,21, a torque wrench with a list of Toyota torque specs, 6ton frame jacks, and a short hydraulic bottle jack, wheel chocks, a set of RAD RUBBER DESIGNS replacement splash shields, SPC UCA's; PB Blaster and anti seize, A good stock of Shiner Bock in the fridge.
TIP: allow twice the time you think you need, take your time and double check your work. Rears take a fraction of the time of the fronts.
Good luck!
AMLOR