[A/S] stablizing jacks

[SHMossLanding@xxxxxxx]

When we purchased our 1965 Overlander, it came with four stablizing jacks.  
My question is what is the location for placement.  I don't see anything 
marked or different on the belly, as perhaps a reenforced pad or the like.  I 
can understand perhaps on the frame at the rear bumper, but where else?

                                                       Thanks,
                                                       Chuck & Lynn
                                                       1965 Overlander