The link you posted has to do with Non PS steering box so different.
I just looked at mine and will say it lifts/lowers maybe 3/32 but not a full 1/8".
I do think it is your locknut #21 in the photo but can't say why the popping. Could be a broken spring washer - #20 that might pop.
Slight chance it is crud preventing the center spool in the hyd block from moving smoothly too.
It's in your hyd block though - pretty sure of that.
If you do go in to the block I strongly suggest that you replace the upper and lower seals - #35 and #14. Upper one especially is a known failure item and will puke oil out from under the steering wheel. Seals, etc not expensive from CNH dealer.
I always replace the 2 orings too - #33
Do you have a manual? It does help to at least have the I&T FO31 manual. It will show proper tightening procedure and staking the nut so it doesn't loosen on you.
Again, they're really not hard to fix. Worst part is pulling the tin.
I have other photos, etc that show where the proper plungers go in the hyd block so if you need it ask.
Glad you have a sense of humor.