Thanks. I think were I got confused was due to the fact that Rock Auto does not carry the 4600s for the rear, only the front. Also, if you search Amazon using 4runner and 4600 it does not yield any results. Turns out the B6 series is the same as the 4600s which does yield a result. I suppose I learned something new.
I guess I wonder how they would be compared to stock ones in working condition. I don't want the truck to ride rough. I bought my truck used with 206k miles and now I have 318k. The ride does seem to have deteriorated in the past year. One of my shocks in the front are leaking. It's looking like my options are the 4600s or the 5100s. Aside from the 5100s raising the front up a bit, I wonder how the rear shocks (4600 vs 5100) compare for stock ride heights?