sjd81,
Don’t worry about the load capacity on your truck. If it came with LT metric tires, you should stay with LT metric tires. P metric tires will not have enough load carrying capacity.
Yes, there is some confusion about tire sizing - and officially, the size includes the letters before and after the numbers. Lt metric tires are built different than P metric tires. Yes, I know you may have some friends who used P metric tires without problems, but I can show you tons of folks who have had problems.
Remember, you said safety is most important! Stick with the LT metrics.