Here are some upper overloads I made for mine 3 years ago . They have held together ( with liberal amounts of anti-seize on the bolts ) and am pleased with their performance . They are easily removable however I usually leave them on as I am almost always loaded . Took them of once last year just to see how they would work .I am not a fan of the lower overloads as I feel they put a point load on the spring pack where it wasn't designed to be . You have to be careful with air bags and not over inflate as that will cause more sway .
https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/25587998/gotomsg/25813847.cfm#25813847