I found mine by following the linkage from the back of the brake pedal.
In cars, this usually goes forward, thru the firewall to the engine compartment.
On my 84 Coachman class c this was true. Under the hood where I expected it.
On my 88 Fleetwood Southwind, the linkage went straight down thru the floor, and the master cylinder was mounted inside the driver's side front wheel, on the frame of the vehicle itself.
Again, the linkage from the brake on your vehicle is likely to go thru the floor or firewall directly to the master cylinder.
Karl I. Sagal KarlSagal@Gmail.com
Well done is better than well said. (Ben Franklin)
1988 Fleetwood Southwind, 34'