Our 1991 Bigfoot
17 came with gas props to support the rock guard. Trouble was, when extended the gas props allowed the rock guard to move. In wind the rock guard bounced up and down, stressing its upper edge and working the piano hinge, the screws that connect the hinge to the body, and the body at the connection.
I knew that part of the problem was the location of the gas props. They are mounted to the body near the piano hinge. Were they mounted further down the body toward the lower edge of the window they would do a better job immobilizing the rock guard.
I decided to have a redundant system. Leave the existing gas props and add telescoping aluminum props. The gas props will hold up the rock guard while attaching the aluminum props.
Angle aluminum "feet" were riveted to the rockguard to hold the aluminum props when in use. A machine screw attached to the prop fits through a hole in the foot. A star knob holds them together. Aluminum U channel, attached with screws, was used for feet attached to the trailer body. I found the telescoping aluminum at an RV supply liquidator in Quartzsite, AZ. A slot was created in the outer tube to accommodate a screw from the inner tube. Wing nuts [later star knobs] on that screw lock the inner and outer tubes.
For storage, the aluminum props pivot on the lower feet to rest against the body in broom handle clips. The rock guard "basin" is deep enough to close over them.