Master Cylinder Upgrade?(hydro-boost )

[DBear]

Hey there.....I need some brake advice. I have a 71 4x4 burb with a 6.2 diesel, and a hydro-boost system ( off an 86 suburban). I am changing out the master cylinder on the unit, and I wanted to change from the cast iron to the aluminum housing/plastic reservoir style master cylinder. To find one with the right bore size, I would have to get one from a 1990 1 ton, and it will bolt up. There are some differences from the cast iron unit I am removing: the small section of the reservoir is in the front, and the large one is the rear. They are reversed from the cast iron one. The brake line fittings are changed as well. As far as I have heard, the small section of the reservoir is always for the rear, and the large for the front.??? If this is true, I can just run the front line fitting (small reservoir) to the rear of the proportioning valve and the rear line fitting (large reservoir section) to the front of the pro. valve??? I am pretty sure the proportioning valve is original to the 71 burb. Can all this work???

[stock75]

*bump* in the same boat any help would be appreciated!