No need to pull radiator off.
Remove clutch fan, accessory belts, balancer and timing belt covers and you are right there, ready to pull the belt.
If it's your first time on a redblock and have mechanical knowledge, budget 4-5 hours for the job. With those miles, I would reccommend replacing the accesroy drive belts too, they're surely due for it, and you have to remove them to get in to the belt.
Also buy the belt kit with idler pulley and crank/cam seals, both seals are easy to replace and should be done at that mileage, I guarantee the crank is weeping a little by now.