Ah i see so you want to prepare for the typical failures . Assuming its a 1KZ-TE -
A new radiator and thermostat would be at the top of my list given the age of your truck .
Lower ball joints are known to fail without warning eventually .
All drive train bushes are probably due renewal .
Steering racks tend to leak eventually and i believe you can get a rebuild kit ?
The metal pipework coming off the fuel tank rusting away has resulted in many a problem , its bolt on and can be bought new .
Rear bumper lights rot and cause electrical havoc .
That's all i can think of with regards to common issues , not bad for a 20+ year old truck .