there is to much slack in the suspension for one x-chock on one side.
i have to use the (2) chocks on the same side. have found if i don't, i just jack the 2 axles the chock is between apart. with a little walking ect. in the trailer, the chock works loose.
with both chocks on the same side, you can tighten all three axles against each other, so the chocks say tight and the trailer doesn't move
i have been considering buying another set of chock so can do both sides.
i tighten the leveling jacks one to two turns after they touch the block i place under them.
have had the front leveled to the point the hitch jack was all the way out and trailer still set solid.
"Then we have these single legged "stabilizer" jacks front and rear"
i also carry blocks to keep jacks closer to the frame. i to have the single leg style. i try to park, so level is with in a bubble right or left. i put as much pressure, on the bolts on the jacks on the, low side as it takes to bring trailer level.
one of the fellows i camp with says this won't work. all i can tell you is, been doing it since 1975 an our first 5th wheel travel trailer.