You may be correct and that’s why I said the advice seems counter-intuitive. However, I believe we ended up at the same place because I doubled the required piston travel in my model. I assumed each piston needs to travel 1/64" (x 2 is .03125). I have no idea if this is accurate. Here’s a link to my Excel file on OneDrive: https://1drv.ms/x/s!AnpOM7cFWalQ0IQjx8LWdn0N56Jh7g
Yes, stock front calipers are a direct bolt-in to the original rear carriers.
Still not concluding anything, but I do believe your assessment that my brake setup is at the very limits of the MC is probably correct. I’m not close to putting it together yet, so some more research and fine-tuning before I make any real conclusion. On the other hand I could just put it all together (which will be in a ~year) and see how it works…but I try to avoid rework scenarios whenever possible.
Excellent article you found, btw. Will have to study that. Wrt volume requirements, it still comes down to running clearance (which I called piston travel). I haven’t found a definitive source for what that should be. I also like the reference to housing stiffness which ties exactly to your analysis on braided stainless lines. At minimum these will be part of my solution and would seem like a requirement.