I looked up the length of your 2018 forest river Flagstaff 29SC and it's 21-1/4 feet long when closed. So for a cover the Adco SFS AquaShed Cover # 290-12252 this can fit up to 5 feet tall in height when the pop up is closed. This figure does not include the AC unit height as all of the covers have that figured in. view full answer...
Without knowing the model of the light that is on the 2018 Forest River Cherokee 274RK I cannot say for sure which lens will fit it. It is possible that the model of the light is on the light body itself, not the lens, but you would likely have to remove the light to see the back of it. Otherwise you would go by the dimensions.
Lens # APL5CB fits # RVPL7C, among other lights. This light is 6-1/4 inches long x 3-7/16 inches wide x 1-7/8 inches deep. If that matches your existing light then... view full answer...
I have actually come across this before and found that the hardware that is used by the Thule Summit cargo boxes was actually an earlier version of the QM3 Hardware, # TH04997 which will work. view full answer...
The Forest River Flagstaff Highwalluses a Dexter Torflex Torsion Axle like you mentioned so we do have a lift kit but this will be dependent on the axle capacity which I was not able to determine. The Torflex Lift Kit part # K71-707-02 for 2,300 to 4,000-lb, part # K71-724-02 for 4,100-6,000-lb, and part # K71-725-02 for 5,500-7,000-lb. view full answer...