Well,
since machining isn’t my strong suit, I went to Aiyama’s place and

made a stopper to attach to the pedal while making all sorts of noise.
Since the Brembo master cylinder has a separate rod, without a stopper it’ll spring up,
and the rod just dangles there.
Well, nobody should install it without a stopper anyway ★

Milled it into a stepped shape and used an M5 ultra-low-head bolt for a flush fit

The eccentric stopper makes contact, so I put in an O-ring to keep it from clicking
Welded a hex rod with a 10 mm flat-to-flat width for easier locking

Ended up with a mesh braid running straight down at 90°
Wrapped the brake hose with braided sleeving and routed the speed sensor wiring inside too
Fewer cable ties

The master cylinder mounting hole is originally M8, so I used a spacer to convert it to M6
You press pretty hard with your heel, so here
a button head or a countersunk head or an ultra-low-head bolt
or your shoes will get totally shredded
To make the master cylinder rod easier to turn,
I punched through a Class 3 M6 nut and tack-welded it.
That’s it.
All that’s left is a test ride and we’re done.