R100RT front brake re-location

Greetings all round, I have a quick question, as part of the restoration process I am relocating the front brake reservoir on my 1980 R100RT from under the tank to the handlebars. please see the attachments . aluminium block at the moment is just sitting there loose on the frame I have not attached yet, It could conceivably go the other way around , and I think the brake hose must lead in forward of the tank bracket support bar, am I right? and what is the wee threaded hole in the top of the block for?
has anyone done this? I'm sure you all have,
any advice greatly appreciated , all the best Heed

Brakes

The input line from the master cylinder should be a straight fitting in the front, not a banjo fitting. That wee hole is tapped for a mount for the electronic ignition control unit that came on 81 and later bikes.

R100RT brake relocation

Thank you Bruce