Bruce Bohannon provides transition training in an RV-8 which he has fitted with rear brakes.
I believe the installation is of his own design and construction. It amounts to a (non-trivial) linkage from (non-stock) rear pedals to the (stock) front pedals to actuate the master cylinders for the brakes.
While I doubt he actually had to use them, I would not have flown with *me* in the front seat without *full* controls including brakes in the rear.
You can contact Bruce (who is based near Angelton TX, south of Houston) at:
(281) eighty eight ninety eight zero 78
flyalegend@gmail.com
BTW: Great instruction received!!
Peter