I stole the hardware off of my ST2 to mount the brake reservoir. I used a 45cc OEM size.
I have some clear hose and Titanium banjo bolts ordered to finish the job.
This is a Medium (30cc) reservoir mounted with some stainless rod (I bought it used). I have a small 15cc resi ordered and I think I make a stronger bracket.
I bent the bracket so that it just clears the top of the dash unit.
I used the Woodcraft clip on handlebar bolt with a spacer under it.