Replacing front brake hoses?

[Stocker]

I'm doing some brake work so it seems like a good time to replace the 40-year-old OEM brake hoses on my '72 K20. Right now I'm just looking at the fronts (will look at rear later). Question is can I replace them by working on the outside of the frame only? Access to whatever is on the inside of the frame channel appears to be pretty poor on the driver's side and much worse on the passenger's side.

As much as I'd like to replace them, in reality if it's gonna be a huge PITA I'll just skip it. Thanks for any help, guys.