NEVER herd of the 4 bolts breaking EVER and if someone says they have, I WILL call BS and ask for proof! Those 4 bolts ARE NOT seeing any real shear stress nor are they seeing much of any other stress EXCEPT at full droop. And even then there isnt a lot of momentum as the uppers dont have a lot of down travel even stock. ADD into the equation that the movement in the ball joint natuarally reduces the stress on the bolts. What you are talking about is when the ball joint its self separates and it DOES NOT matter if the ball joint is mounted on top or bottom of the a-arm. If the ball joint separates the top of the spindle is going to be loose no matter where the ball joint is bolted to the arm. The ball joint will separate long before those 4 little bolts break.
And you NEVER hear of the 4 little bolts breaking.
Really depends on the back space of the wheels. I have flipped ball joints and 15" wheels and not even close to rubbing but I do believe the stock 16's will rub due to their backspace/offset.
And to the original poster looks good man and should help a lot with the ride it looks as though you was riding right on the droop stops before.
I, myself, have actually had the experience of the 4 bolts breaking. Went on an easy wheeling trip, when we stopped for lunch, I noticed that one of the bolts was gone. Continued down the trail, because I still had 3 bolts left and it was the only way home. Couple miles down the trail, we heard a "ping-ping" and the front wheel folded in. The other 3 bolts all sheared at the same time, driving straight on a dirt road. I don't attribute it to poor design or a result of my balljoint flip or my lift kit, I actually think that the bolts in my replacement balljoints where just Chinese and not up to the task.
I felt the need to chime in, because somebody said that it "never" happens and it happened to me. There is no problem with the bj flip, it is just harder to align sometimes, but it can help the upper ball joint live longer too.