One thing I would do if I were you, double-check those pins you have in the lower links. If the sticker on them does not say that they are forged, return them and buy the forged version.
If not, if you go to get them really tight the beveled ring on the pin side that the nut snugs up to will slip and move towards the pin side.
I had that happen on a three-point hitch single tooth ripper. I took it back and asked if I could just get enough of a refund to get forged pins, but they wouldn't do that.
They replaced the whole thing and then before I left the store, I purchased a pair of forged pins to replace the ones on the bottom links.
Aaron Z