I have also heard of guys using an empty .22 shell casing over the pin to make it reach. Alternately you could just get a new pin and spring from Toyota.
There are 3 small screws behind the steering wheel that take the cover off the face of the steering wheel, the surround for the horn buttons, then you could see the wires that go from button to the contact pin. MANY, MANY, MANY fj60 have had...
Just curious, why disable the auto off feature. Are you worried about wearing out your starter motor prematurely or just the start/stop thing creeping you out? Do you think Toyota installed these to say how they are "earth friendly"? Maybe...