replacing brake master cylinder with wilwood with body on

[GoDadGo]

Be advised that you likely will have to move some wiring around which you may or may not be thinking about, assuming that the fuse block is in the stock location.

When I started my build I considered using that Mustang pedal assembly instead of the Wilwood set up.
I even went to the extent of moving the fuse block to the passenger side of the car.
The bottom line, I'd keep what you've got since it is more easily serviced.