JoeBob, you should be fine, but if I were you get it replaced if you can. I must warn you though...there is a sizeable water crossing on this trail and there's nothing worse then water getting into a torn boot. If you are replacing the entire CV then no worries, but if you are doing just the boots that would be bad. Although with the clicking noise it sounds like the CV is bad already.

When you are testing the CV in 4wd are you on dirt or pavement? Hopefully pavement, as your 4wd system won't like being engaged on dry pavement and will make turning hard + clicking noises.

BTW, lowering your truck shouldn't be too hard if you know how to adjust the t-bars.