Hi Keller, The lower leg is retained by the brass plate & worm gear that is peened in the top of lower leg... Mine was not done well as it pulled free by me trying to drop leg with the release lever... The worm gear screws into this plate... I don't believe you had this in your pic's... I don't have a way to peen it so am thinking of drilling for roll pins as it could come out during use & needs to B taken off to reinstall it...
If others R like that (not well peened) the leg could come down at any time... I have drilled a hole at the bottom & put a screw in each jack to prevent any coming down. NOTE with remote!!
P.S. This was/is a smooth operating jack...