Hydro-boost questions (looking for data)

Looks like Wilwood makes a nice one. Looks like pretty much a bolt on unit.

New 1966-1970 Chrysler, Dodge, Plymouth Charger Hydro-Boost Brake Booster

This is a nice system but its $450 (just the HB unit, everything else is extra). You can buy a HB unit off Rock Auto for $122 - $200. I am trying to determine what is different between those listed/made for a car over something off RA. Obviously it would be the mounting system and the rod; I am fully capable of making or altering both of those items so I am really trying to determine what is the best course of action; which unit is the best to start with, etc.

I am leaning towards a Dodge diesel unit, one because its Mopar but more so because I want to use a Mopar MC and I know it will bolt up. What I am unsure of is the mounting plate (can I remove it or alter it) and the rod (can it be removed).