Normally an engine this old that needs a new timing chain, also needs an overhaul. I cannot tell you in this limited space how to change the chain and gears. I suggest you purchase a Haynes, or Chilton's repair manual.
If the engine is a 3.0 or 3.8L V6 it has timing chain and Gears.
replace the chain and gears
SORRY, But it don't have a timing belt. It has timing chain and gears.
Replace the chain and both the cam and crankshaft gears.
All timing gears. You have to disassemble the entire front of the truck and engine to access.
Timing gears
That engine has a timing chain and gears and will probley out last the engine. NO need to replace it.
Remove everything in front of the timing cover. Loosen the oil pan. Remove the timing cover. Replace the chain and gears by lining up the dots on the old gears and installing the new gears with the same alignment. Clean everything real good and put it all back together.
It has a chain and gears. NO BELT. There would be no reason to fool with the timing chain and gears on that year engine. The chain and gears would out last the engine.
It has a timing chain and gears.
it has both chain and gears
It has a timing chain and gears. NO timing belt.