They make an adjustable foot that you put on one side that allows you to set both legs with the same pressure. This system works great, I bought mine at camping world.
My fiver has springs between the axle and frame that allow for slight or major differences in the ground plane! I just drop the inner legs and jack it up!
Barker makes a "5th wheel leg leveler" that is cool. You only use one on the jack nearest to the switch. For uneven ground you would extend the jacks normally and when the other one makes contact with the ground you adjust the leg (with the leveler) by spinning it until it makes contact with the ground, then you extend the jacks as usual. It allows both jacks to extend evenly without having to use wood etc.
Wow, after reading all of this I'm afraid I've just been making a molehill out of a mountain all of this time. Here I doing it simple when I was suppose to be doing it complex. Pull pins, let each leg fall to ground (or 2X if wanted); push each leg up until pins engage; raise off of truck. Hmmmm guess I'm just too simple minded. Must be government involved here somewhere.
Dave & Dee
2006 40' Open Road
2008 F-350 Dually V-10 4:30
2 yrs USA Big Red One Vietnam Retired USAF
Retired teacher after military