Dexter has a kit, got mine from amazon. Do a google search for dexter axle flip kit. I have lippert axles too and it went in like a cinch. Make sure you measure the diameter of your axle as there are two sizes. I dragged my spare tire last trip last season and vowed I fix it. The kit lifted my trailer about 3".
*** maybe I should clarify cinch. It was a two day project for me. Day one set up jack stands and supports plus go through tools/supplies to make sure I don't have to run to the store. Day two do flip also install new wet bolts in suspension kit with new tires. I have a welder so I was able to tack the new supports in place. Also had time to paint the rock chips and rust with rust converter and flat black. Lastly, open favorite malted beverage and survey work.
Re: improperly rated axles, mine are 3000# x2 for 6000# which is perfect for my 5900#MGTW trailer.