Take a look inside of the green 411/412 to 1974 Haynes manual at the layout for the power brake system.
Depending on how you want to feed things is how you will install things.
Basically on the power brake system they punched out the pressed into teh body depression fro teh pushrod hole. Then....they made a metal bracket to angle the master cylinder down so it is level.....so it would not hit against the hood and they could use a bus style resovoir on top of it.
This bracket does not have to be too stiff. It certainly wouldn't have tp be much stiffer than how any other master cylinder is mounted on a sheet metal fire wall.
The things to make are a short "A" frame bracket that bolts to teh brake pedal framework under the dash....in the two bolt holes where teh master cylinder used to reside.
Since when you push the pedal in a type 4....it pushed teh pushrod back towards the driver, you will now flip it around ....so when you push teh pedal....it pulls the rod facing forard. That rod is hooked to a metal disc...preferably steel...riding on an axle (a shoulder bolt...thick)mounted to the bracket you have made. The pushrod from the pedal is attached at the say....6:00 position on the metal disc. The the rod contacting the master cylinder is attached anywhere from 11:00 to 1:00 on the top of the disc. When you push the pedal, the pushrod pulls back toward you. It rotates the steel disc.....clockwise. That means that the other pushrod at 11:00 to 1:00 position roatates forwad (clockwise) as well...pushing on the cylinder.
You can make the stroke quicker...meaning less pedal travel but more leverage required...by drilling extra holes and moving the upper pushrod closer to the axle in the middle.
This works like this: So the steel disc is about 4" diameter: The pedal rod it attached at 6:00 position but 1/2" from the outer edge. The upper master cylinder rod is connected at 12:00 and 1/2" from the outer edge.
Lets say for instance that if I push on the pedal with this set up....it rotates the disc 90*....and in this set up....the upper pushrod moves the exactsame distance as the lower one. Because it is exactly 180* from the lower pedal pushrod...and the same distance/diameter from the disc pivot point. They are in 1:1 Ratio in this position. With me so far?
So if I wanted a shorter pedal stroke...say half the pedal travel.....drill another hole in the disc....still in the axis of the 6:00 position....but move it inward toward the pivot point of the disc. Move the lower pushrod from the pedal to this hole. It is now effectively stroking in an arc diameter od say...a 2" disc....instead of a 4" disc. Every mm of pedal travel is now twice the distance of master cylinder pushrod travel. In this case it is now 1:2 ratio.
You will need to get couplings to join a new metal line to each old master cylinder brake line. They go out through the holes in the firewall where the original resovir fluid hoses came in...with grommets. You will need a connection from the master cylinder resovoir with a hose going back in the third hole to connect to the clutch slave.
Installation of all of this is an afternoon. But you first have a bit of mocking up and trial fitting to do. Ray