Thanks for your reply. I will look at those shocks. I am using OME 2934 springs they measured to a 20" free length also. I currently have Rancho RS55128 shocks and they seem to be to short. Springs measure 14.5" at ride height. At full bump I still have 2" of shock shaft left. This is the first time I have tried to piece together my own lift and I appreciate the advice.My focus will goto the free length of the coil @2.5" to keep them seated. Rough country progressive has the longest 2.5" coil @20" which is the same and a tad more than most 4" lift springs. They can be set up with 11" travel using shock relocation towers.
24.5" extended shock length unseats the 20" freelength front springs. I most often use the 180 5100 seires and 337 5125 bilstein. 5125's mount can up and do not come with a barpin.
You'll find ome N66L have a 15.5/26.5" length. The springs will be unseated nearly 3".