hydraulic brake actuation

Am researching the brake system for my glider project and am pretty
sure a disc brake is the way to go. The cost for a suitable drum brake
is about 2x what a disc brake from Grove or Matco costs, Azuza makes
drum brakes, but they don't seem robust enough for my needs.

I plan on using a bike grip type handle to actuate the brake, not a
problem with a drum brake, but not so easy with the disc brake, as far
as what I have been able to find out. There is a stick mounted hand
grip style Matco makes, but it has the reservoir attached and will
interfere with my control stick geometry.

What I am leaning towards is a bike grip, with the cable running to a
lever with mechanical advantage to actuate the hyrdraulic master
cylinder. (DRN.........you sent me a pic of this?)

Do any of you guys out there with disc brakes have a bike grip type
actuator? and how does it actuate the master cylinder?

Do not want to brake actuated by the airbrake circuit, nor a heel
brake.

I did a search of this group on this subject, and did find some useful
info, but wanted to start a more specific thread..................ok,
so I am lazy!

TIA,
Brad