An extra pair of jacks near wheels will make a big difference. If you want to go a step farther, you could use the BAL locking arms. One end attaches to the bottom of the rear jack and the other end attaches to the frame. There are at least a couple of other manufacturers that make a similar product. I don't know much about them but am considering them for our TT. I think you only near a pair at the rear but I would think that a side to side one would be needed as well? Another tip is to use some tall blocks under your jacks so they don't actually extend that much.
Anyone know if an electric jack will fit between or near the wheels? We have elec. front and rears and it seems like a step backward to put something manual in there....
Bal locking arms