I use two (added a second bc it works so well) of these from REI, called "Beach Tents" Square lycra type material, corner rivets with elastic rope for tie downs on each corner in addition to two aluminum poles (imagine a pup style tent)...
Instead of using them as a tent, I tie them down on the SMB and then stretch them and tie down with screw in the ground leash handles or to anything handy/sturdy to form the makeshift awning...you can buy additional poles (added two taller poles)for even better options ...can be extended/held on tire rim/tire etc...They are 'break apart' aluminum poles with elastic inside, one end is a hard flat plastic piece size of a half deck of cards, and the other end is a rubber like ball to stretch into and protect fabric. Poles stay in place bc of the stretching for tautness on fabric...all breaks down into a bag size of a small backpack...$150 and $185 for the bigger one...i could only find a pic of the blue one...I'll try to find a link
'13 MDX 'BigBlackmobeebs'
'01 Lexus 430 LS 'Luxobeebs
'20 Tacoma TRD OR 'Tacobeebs'