I finally made some lowers-Foot warmers

Maybe you could use something like this to keep the cost down? And it would not damage the crash bars?
 
Yup...I know about those clamps, but that would have to be someone else's choice. Someone else used them and although functional, they looked tacky in my opinion. Hard to beat the appearance of the Kuryakyn Clamps...plus a flat head screw locks them in place without the main screw going through them. Once in position they stay in position when I remove the uppers for summer.

As for damaging the crash bar, a simple solution is to cut a thin 1/2” wide strip of aluminum from a piece of dryer vent material. Neatly wrap it around the bar before the install and no marks. As for me, I doesn’t matter as they are not coming off. With the top part removed for summer I’m already thinking about some lower running lights to make use of those two upper P-Clamps.