Having the tool makes the job a snap, but there are other ways.
One that works very well is the "rope trick".

It works like this:

Get a length of rope that will fit through the spark plug hole. when you get ready to remove the crank bolt, remove the spark plug(no.1). Turn the engine til no.1 piston is coming up for the compression stroke. Stop just before it reaches TDC and stuff enough of the rope into the combustion chamber to keep the piston from reaching the top. That will hold it good enough for you to apply the torque necessary to remove the bolt. Use a braker bar.

When you replace bolt just reverse the procedure(turn engine in opposite direction). Works great. Make sure the engine is on the compression stroke! If not, you will bend a valve. Put your thumb over the spark plug hole, you will fill the pressure building inside the combustion chamber as the piston rises.

also, check the 700 faq under timing belt, you'll find more.

Luck

LS.