I've got the Mustang Vintage Wide Touring seat and am wondering if this will work well with the Harley Med Low sissy bar or do I need to go up to the low (yes the low is taller than the medium low) sissy bar for clearance. Anyone know for sure? It looks like it would work but you never know.

 

I have used a short rail detachable sissy bar with mine. It comes about 4 inches over the passenger pad.

 

I forget which sissy bar I got, but the mustang and the sundown seat are about 3.5 inches tall for the passenger, so you want the backrest pad above that.
Mine sits just at the seat level (they touch) and the wife likes it.

The Harley dealer helped me out, as I wanted the lower one, but got the next one up.

Brett