When you, like me, are using a pure race brake master cylinder, then the original mounting for the fluid reservoir doesn’t fit. I have never been able to find a good alternative so I copied this design from a friend of mine. What you need is a small piece of alloy, make it “z” shaped, drill a hole in the upper front fork triple clamp and fit an M4 bolt. Just remember to use thread lock.
I have had this design on my previous Ducati race bikes. One particular feature that I like is how well protected those reservoirs are when you crash. And yes I know from personal experience. :-)
Cost efficient, works well and I think it looks good too!