Jim, the scissor jacks may not be the answer. Ask anyone that has had them on a TT, the back end still moved around quite a bit. There is a lot of movement in them, especially when extended as far as you will need them. Bottle jacks are the cheap answer. If you are at all handy, you may be able to fab some right triangle braces to bolt the frame and extend out to the side of the MH, if there is room, to place the jacks under to easily use the jacks, without having to crawl under to install and retrieve the jacks every time you need them.