The options got narrowed down pretty quickly and I ended up moving the master about 2 1/4" down on the firewall after rebuilding the mounting plate and then fabricating a new linkage. Time will tell if the "throw" and pedal ratio are going to be correct and/or comfortable. I may be getting back in there to make more alterations as I see how well it works.
Thanks for the ideas. Always helps to bounce these things off 6 or 8 folks who know what they are doing.
(I'm still wondering how that reservoir comes apart - so feel free to continue the thread if you've got the answer, or even a good guess. It's a matter of satisfying my curiosity now.)