My heated bed connector is in the back of my printer, so back sensor mounts tend to hit the connector during print. I therefore created this front/left mount which mounts to the outside of the of the fan.
The slots for the barrel were purposefully oversized to ~9mm with slots so no post processing was required.
I'll be honest, I assumed the fan screws were 45 degrees from horizontal...They're not. So it has a slight lean to it, but functions very well. Drop a tower of Pisa in with your slicer to get an intentional look.
Marlin firmware code for offset: